SLACspeak
Glossary of SLAC-related abbreviations, acronyms, initialisms, terms and lingo
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1/ab Inverse attobarns. An inverse attobarn corresponds to one billion pairs of particles (ex. one billion pairs
of B and anti-B particles produced at SLAC by the PEP-II accelerator).
29 CFR The title within the Code of Federal Regulations which contains requirements pertaining to worker health and safety as
promulgated by OSHA.
2DEG 2-Dimensional Electron Gas.
2DFGRS Two Degree Field Galaxy Redshift Survey.
2HDM two Higgs-Doublet Model
2HSM Two-Higgs Standard Model
2PACL 2-Phase Accumulator Controlled Loop.
4f-HRM 4f-High Resolution Monochromator (LCLS-II-HE)
40 CFR The title within the Code of Federal Regulations which contains regulations pursuant to many environmental laws, most
notably RCRA.
49 CFR The title within the Code of Federal Regulations which contains regulations pertaining to the transport of hazardous
materials as promulgated by DOT.
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A Angstrom.
A DC steering magnet.
A&E Administration and Engineering. (Building 042)
A/D Analog to Digital.
A/E Acquisition Executive.
AAA Advanced Accelerator Association for promoting science and technology.
AAA Authentication, Authorization, and Accounting
AAAS American Association for the Advancement of Science
AAM Annual Actual Maintenance
AANM Astronomy and Astrophysics in the New Millennium. (2001)
AAP Accelerator Advisory Panel. (ILC)
AARD Advanced Accelerator Research and Development
AARP Advanced Accelerator and Radiation Physics.
AAS American Astronomical Society.
AAS Advanced Accelerator Studies.
AB Assembly Bill.
ABA Aetron-Blume-Atkinson (Aetron Division of Aerojet-General Corporation; John A. Blume and Associates, Engineers; and
the Guy F. Atkinson Construction Company), joint venture involved with the construction of SLAC
ABAG Association of Bay Area Governments.
ABC Abashian-Booth-Crowe
ABEL EPA's computer model for analyzing a violator's ability to pay a civil penalty.
ABF Andrews-Baxter-Forrester
ABJ Adler-Bell-Jackiw anomaly.
ABL Aharonov-Bergmann-Lebowitz
Absolute zero Zero on the Kelvin and Rankine scales.
See WORD-OF-THE-WEEK at http://today.slac.stanford.edu/a/2008/04-11.htm http://today.slac.stanford.edu/a/2008/04-11.htm.
AC Air Conditioning or Air Conditioning unit.
ACC ACCounting Office.
Accelerator Device used to produce high-energy beams of charged particles such as electrons, protons, or heavy ions for
research in high -energy and nuclear physics, synchrotron radiation research, medical therapies, and some industrial applications.
Accelerator A particle accelerator uses electric fields to propel subatomic particles to speeds rivaling that of light.
Accelerator Status See ACCS.
acceptance A measurement of the size of the beampipe aperture as applied to generalized parameters such as energy, angle,
and transverse positions. The units of acceptance are the units of the particular parameter whose acceptance is being
measured or defined. Geometric acceptance is the emittance at which 90% or some arbitrary fraction of the beam is transmitted
through the available aperture. Energy acceptance is the energy range at which 90% or some arbitrary fraction of the beam
energy is transmitted through the pipe. See also Emittance.
Accident Site The location of an unexpected occurrence, failure or loss, either at a plant or along a transportation route,
resulting in a release of hazardous materials.
ACCMM Altarelli-Cabibbo-Corbo-Maiani-Martinelli
ACCMOR Amsterdam-CERN-Cracow-Munich-OxfoRd
ACD Advanced Conceptual Design.
ACD Analytic Continuation by Duality
ACD Anti-Coincidence Detector (GLAST).
ACDS Administrative Controlled Document System. (SLAC)
ACE Astrophysical Composition Explorer.
ACE3P Advanced Computational Electromagnetics 3-D Parallel. A software suite used to run accelerators.
ACFA Asian Committee for Future Accelerators.
ACGIH American Conference of Governmental Industrial Hygienists. This group is best known for developing TLVs for
occupational chemical exposures.
ACH Air Changes per Hour. The movement of a volume of air in a given period of time. If a house has one air
change per hour, it means that all of
the air in the house will be replaced in a one-hour period.
acid A large class of substances having a pH less than 7. An acid waste is considered hazardous when its
pH is 2.0 or less.
ACKS Astro/CSSA/KIPAC/SLAC (Seminar series).
ACL Alternate Concentration Limit or Administrative Control Level.
AC-LEEM Aberration-Corrected Low-Energy Electron Microscope.
ACM Asbestos Containing Materials
ACP SSRL Accelerator Systems Department, Accelerator Development and Controls Group.
ACR Accelerator Control Room. (Building 052)
ACS Access Control System.
ACS Advanced Computing Services
ACSR Advanced Science Computing Research. (DOE)
ACT Agreement for Commercializing Technology. DOE
Activated Carbon A highly adsorbent form of carbon used to remove odors and toxic substances from liquid or gaseous emissions. In waste
treatment it is used to remove dissolved organic matter from wastewater. It is also used in motor vehicle evaporative control systems.
Activated Sludge Sludge that results when primary effluent is mixed with bacteria-laden sludge and then agitated and aerated to
promote biological treatment. This speeds breakdown of organic matter in raw sewage undergoing secondary waste treatment.
Activated Sludge Treatment Exposing waters to microorganisms and air. A portion of the organic matter is oxidized to carbon dioxide and
water and the other portion is synthesized into new microbial cells.
ActiveX A loosely defined set of technologies developed by Microsoft. ActiveX is an outgrowth of two other Microsoft technologies, called OLE
(Object Linking and Embedding) and COM (ComponentObject Model).
ACTS see DOE ACTS
Acute Effects Toxic effects which occur over a relatively short period of time (minutes, hours). See also Chronic Effects.
Acute Toxicity A quantitative measure of the effects of a toxic agent administered once or only a few times over a short period of time, e.g.,
24 hours. See also Chronic Toxicity.
ACWP Actual Cost of Work Performed.
AD Associate Director.
AD Active Directory.
AD Accelerator Directorate
ADA Americans with Disabilities Act.
ADC Analog-to-Digital Converter.
ADC Tolerance See ATOL.
ADD Arkani-Hamed, Dimopoulos, and Dvali (1998)
Address Resolution Conversion of an Internet address to the corresponding physical address.
Address Resolution Protocol See ARP.
ADE ADE refers to the A_n, D_n and exceptional E_n Lie Groups. These are the Lie groups with only single lines in
their Dynkin diagrams.
ADEPT Advanced Dark Energy Physics Telescope.
ADHM Atiyah-Drinfeld-Hitchin-Manin.
ADHMN Atiyah-Drinfeld-Hitchin-Manin-Nahm.
ADI Angular Differential Imaging.
ADM Arnowitt-Deser-Misner
Administrative Order On Consent A legal agreement signed by EPA and an individual, business, or other entity through which the violator
agrees to pay for correction of violations, take the required corrective or cleanup actions, or refrain from an activity. It describes the
actions to be taken, may be subject to a comment period, applies to civil actions, and can be enforced in court.
ADMO Accelerator Division Maintenance Office.
ADs Associate Directors.
ADS Activity Data Sheet.
ADS Astrophysics Data System. (SAO/NASA)
ADS Accelerator-Driven machine concept. (Europe)
ADSL Asymmetric Digital Subscriber Line. A technology that allows more data to be sent over existing copper telephone lines. ADSL
supports data rates from 1.5 to 9 Mbps when receiving data (downstream rate) and from 16 to 640 Kbps when sending data (upstream rate).
ADSO Accelerator Directorate Safety Office.
Adsorption Gathering a gas, liquid, or dissolved substance on a surface (e.g., charcoal adsorbs gases.) Can be used to remove low
concentrations of organic materials from gaseous and watery waste streams.
ADST Asymptotic Disappearance of Space-Time.
ADTT Accelerator-Driven Transmutation Technology
Advanced Projects Research Agency See ARPA.
Advanced TCA Advanced Telecommunications Computing Architecture.
Advanced Wastewater Treatment Any treatment of sewage that goes beyond the secondary or biological water treatment stage and includes the
removal of nutrients such as phosphorus and nitrogen and a high percentage of suspended solids. See Primary Waste Treatment and Secondary Treatment.
AdvLIGO Advanced Laser Interferometer Gravitational-wave Observatory.
AED Automated External Defibrillator.
AED or AE Accelerator Engineering Division.(SLAC)
AEESP Association of Environmental Engineering and Science Professors.(Canada)
AEG Alignment Engineering Group
AEL Accessible Emission Limit.
Aerobic Occurring in the presence of free oxygen.
aerogel extremely light, diaphanous substance
AES Auger Electron Spectroscopy.
AFB Air Force Base
AFF Above Finished Floor.
AFFF Aqueous Film-Forming Foam. Contains fluorocarbon surfactants to change the surface tension of water such that it will float on
hydrocarbon compounds in which it would normally sink, thereby enhancing firefighting.
AFM Atomic Force Microscopy.
AFP Approved Funding Plan.
AFS A widely used Unix network file facility allowing file sharing among machines many thousands of miles apart. AFS is descended
from a distributed file system developed at CarnegieMellon University and was originally called the Andrew File System in honor of
Andrew Carnegie.
AG Alternating Gradient.
AGASA Akeno Giant Air Shower Array.
AGC Automatic Gain Control.
AGK Abramovskii-Gribov-Kancheli
AGUT Anti-Grand Unification Theory.
AH Air Handler.
AHA Area Hazard Analysis.
AHERA Asbestos Hazard Emergency Response Act of 1986. (Federal)
AHRO Archives, History and Records Office (SLAC)
AHJ Authority Having Jurisdiction.
AHM Acutely Hazardous Material. (CH&SC Sec. 25532 et seq)
AHU Air Handler Unit.
AI Artificial Intelligence. The branch of computer science that studies how smart a machine can be, which involves the capability
of a device to perform functions normally associated with human intelligence, such as reasoning, learning, and self-improvement.
AI Accelerator Improvements. A class of DOE funding.
AIB Accident Investigation Board
AICHE American Institute of CHemical Engineers.
AIDA Accelerator Integrated Data Access. A software service in the accelerator complex, which allows scientific software
applications to access the various kinds of data necessary for control and optimization of the beam. For instance, control
data, mathematical models , archived data, static data in Oracle, etc. See http://www.slac.stanford.edu/grp/cd/soft/aida/.
AIDA Advanced european Infrastructures for Detectors and Accelerators.
AIHA American Industrial Hygiene Association.
AIL Agreement of Associated International Laboratory (France and Japan ).
AIP American Institute of Physics.
AIR Advanced Instrumentation for Research division. (SLAC)
Air Changes per Hour See ACH.
Air Pollutant Any substance in air which could, if in high enough concentration, harm humans, other animals, vegetation,
or material. Pollutants may include almost any natural or artificial composition of matter capable of being airborne. They
may be in the form of solid particles, liquid droplets, gases, or in combinations of these forms. Generally, they fall into
two main groups: 1) those emitted directly from identifiable sources and 2) those produced in the air by interaction between
two or more primary pollutants, or by reaction with normal atmospheric constituents, with or without photoactivation.
Exclusive of pollen, fog, and dust, which are of natural origin, about 100 contaminants have been identified and fall into
the following categories: solids, sulfur compounds, volatile organic chemicals, nitrogen compounds, oxygen compounds, halogen
compounds, radioactive compounds, and odors.
Air Quality Control Region An area--designated by the federal government--in which communities share a common air
pollution problem. Sometimes several states are involved.
AIS Advanced Instrumentation Seminars.
AJAX Asynchronous Javascript and XML.
AKHEP Association of Korean High Energy Physicists.
AKNS Ablowitz-Kaup-Newell-Segur
AL Ablowitz-Ladik
ALARA As Low As Reasonably Achievable.
ALBA New third-generation synchrotron light source located near Barcelona, Spain.
Alcove A room located in each klystron gallery sector housing a micro and other controls and hardware for a LINAC sector.
The areas housing electronics in the arcs are also called `alcoves.'
ALCPG American Linear Collider Physics Group.
ALCSC Asian Linear Collider Steering Committee.
ALCTS Association for Library Collections and Technical Services.
ALD Associate Laboratory Director (SLAC)
ALD Atomic Layer Deposition.
Alderson phantom A human skeleton enclosed in plastic tanks filled with tissue-equivalent liquids containing the
0 same trace elements as are found in human bodies. Used under controlled conditions to safely determine radiation exposure.
ALF Left-Right Asymmetry (measurement in Z interactions)
A-Line The transport line from the beam switchyard (BSY) to End Station A (ESA).
ALLM Abramowicz-Levin-Levy-Maor
ALMA Atacama Large Millimeter Array telescope. (Chile)
ALP Annual Laboratory Plan.
ALP Axion-Like Particle
Alpha Generally refers to a Twiss parameter measuring the rate of change of Beta, used in studies of accelerator optics.
ALPHA Antihydrogen Laser PHysics Apparatus.
Alpha Magnet A dipole magnet designed to bend the beam through a sharp angle (in the shape of the Greek letter Alpha). For example,
an alpha magnet is used to bend the beam out of the NPI injector back into the linac
ALPS Any Light Particle Search. (DESY)
ALS Advanced Light Source.
ALS Advanced Life Support.
ALTA Alberta Large-scale Time-coincidence Array.
Alternating Gradient Focusing Magnet See AGF.
AMANDA Antarctic Muon And Neutrino Detector Array
AMBER Advanced Materials Beamline for Energy Research (LBNL)
AMD Antisymmetrized Molecular Dynamics.
American Conference of Governmental Industrial Hygienists See ACGIH.
American National Standards Institute See ANSI.
AMO Atomic, Molecular, and Optical physics.
AMOS Atomic, Molecular, and Optical Science
AMS Alpha Magnetic Spectrometer (PSI). An experiment to detect antimatter and dark matter in space.
AMS Acquisitions Management System. (Purchasing)
AMSB Anomaly Mediated Symmetry Breaking.
Angstrom An angstrom is a very tiny unit of measure equivalent to 10-10 meters, or about the average distance between
individual atoms. It's commonly used to describe the lengths of chemical bonds and wavelengths of light, such as X-rays. The Linac
Coherent Light Source produceS "hard" X-rays with a wavelength of 1.5 angstroms, giving it the power to make images of objects
on the atomic scale.
ANITA ANtarctic Impulsive Transient Antenna.
ANL Argonne National Laboratory.
Annihilation See WORD-OF-THE-WEEK http://today.slac.stanford.edu/a/2008/10-31.htm
Anonymous FTP A method for downloading public files using the File Transfer Protocol (FTP). Anonymous FTP is called anonymous
because you don't need to identify yourself before accessing files.
ANP Adler-Nussinov-Paschos.
ANS American Nuclear Society.
ANSI American National Standards Institute. The Institute disseminates basic standards like ASCII, and acts as the United States'
delegate to the ISO. Standards can be ordered by writing to the ANSI Sales Department, 11 West 42nd Street, New York, NY 10036,
or by telephoning 212.642.4900
Antagonism The interaction of two chemicals having an opposing, or neutralizing effect on each other, or--given some specific
biological effect--a chemical interaction that appears to have an opposing or neutralizing effect over what might otherwise
be expected.
Antibodies Proteins produced in the body by immune system cells in response to antigens, and capable of combining
with antigens.
Anti-Degradation Clause Part of federal air quality and water quality requirements prohibiting deterioration where pollution
levels are above the legal limit.
AO Adaptive Optics.
AOD Analysis Object Data.
AOFSRR Asia Oceania Forum for Synchrotron Radiation Research.
AOPDF Acousto-Optic Programmable Dispersive Filter (the Dazzler).
AOS Array Operations Site. (ALMA telescope - Chile).
AOS Accelerator Operations and Safety. (SLAC) See Also AOSD.
AOSD Accelerator Operations and Safety Division. (SLAC Accelerator Directorate)
AP pulse steering magnet.
AP Accounts Payable
APAC Asian Particle Accelerator Conference.
Apache Web Server A public-domain Web server developed by a loosely knit group of programmers. The first version of
Apache, based on the NCSA http daemon Web server, was developed in 1995. Because it was developed from existing NSCA code
and various patches, it was called a patchy web server. Sophisticated features, excellent performance, and low price
(it's free), have made Apache the world's most popular Web server. By some estimates, in 1999 it hosted more than
50% of all Web sites in the world.
APAF Advanced Plasma Acceleration Facility. (proposed)
APB Administrative Panel on Biosafety. (Stanford University)
APCA Air Pollution Control Association.
APCD Air Pollution Control District. (CH&SC Sec. 40000 et seq)
APE Array Processor Elements, a European project involving INFN, DESY, and the University of Paris-Sud.
APEL Accounting Processor for Event Logs.
APENext Array Processor Experiment/Next. (Supercomputer)
Aperture In optics, the effective diameter of a lens or mirror. In accelerator terminology, a measure of
the transport line's effective opening.
API American Petroleum Institute.
API Application Program Interface. A set of calling conventions defining how a service is invoked through
a software package.
APM Assurance Program Manager.
APPEC AstroParticle Physics European Coordination.
Applet A dynamic and interactive program written in the Java language, which can run inside a Web page displayed by a
Java-capable browser.
Application Layer The top-most layer in the OSI Reference Model providing such communication services as
electronic mail and file transfer.
Application Server A server dedicated to running specific applications (for example, a communications server).
APS Advanced Photon Source (x-ray facility) at the Argonne National Laboratory near Chicago, Illinois.
APS American Physical Society
APT Accelerator Production of Tritium
APT Advanced Persistent Threat. (Computing)
APU Atomic Parity Violating
AQMD Air Quality Management District.
AQS Air Quality Standards.
Aqueous Film-Forming Foam See AFFF.
Aquifer A geologic formation that contains sufficient saturated permeable material to yield
significant quantities of water to wells and springs.
AR Assisted Reality.
AR Augmented Reality.
ARA Accelerator Research Department - A
ARAA Annual Review of Astronomy and Astrophysics.
ARAC Atmospheric Release Advisory Capability.
ARB Air Resources Board. (CH&SC Sec. 39500 et seq)
ARB Accelerator Research Department - B
ARCADE Absolute Radiometer for Cosmic And Diffuse Emission.
ARCAS Arillaga Recreation Center At SLAC.
ARD Accelerator Research Division (SLAC).
ARDA Accelerator Research Department A (SLAC)
ARDB Accelerator Research Department B (SLAC)
Area of Review In the UIC program, the area surrounding an injection well that is reviewed during the permitting process to determine whether
the injection operation will induce flow between aquifers.
Area Source Any small source of non-natural air pollution that is released over a relatively small area but which cannot be classified
as a point source. Such sources may include vehicles and other small fuel combustion engines.
ARF Ancillary Response Files.
ARG Accident Response Group.
ARGO Astrophysical Radiation with Ground-based Observatory. (Tibet)
ARGOS Advanced Research and Global Observation Satellite. A US Air Force low earth orbit satellite launched in 1999 carrying the USA
experiment (among others).
ARL Archives and Research Library.
ARM SSRL Accelerator Systems Department, Accelerator and FEL Physics Group.
ARO After Receipt of Order
ARP Address Resolution Protocol. The Internet protocol used to dynamically map Internet addresses to physical (hardware) addresses on local
area networks. Limited to networks that support hardware broadcast.
ARPA Advanced Research Projects Agency. Former name of DARPA, the government agency that funded ARPANET and
later the DARPA Internet.
ARPANET A pioneering long haul network funded by ARPA. It served as the basis for early networking research as well as a central backbone
during the development of the Internet. The ARPANET consists of individual packet switching computers interconnected by leased lines.
ARPES Angle-Resolved PhotoEmission Spectroscopy. Technique pioneered at Stanford and at SLAC to study the behavior of complex materials.
Uses a high-resolution spectrometer to detect electrons emitted from the surfaces of materials subjected to intense X-ray beams.
ARR Accelerator Readiness Review.
ART Algebraic Reconstruction Technique
ARTEMIS Accelerator Remedy Trouble Entry and Maintenance Information System.
Artesian Aquifer An aquifer in which ground water is confined under pressure significantly greater than atmospheric pressure. Also known as a
Confined Aquifer.
Artificial Intelligence See AI.
AS Australian Synchrotron. GOV
ASACUSA Atomic Spectroscopy And Collisions Using Slow Antiprotons. A Japanese-European collaboration at CERN. (Also the name of a famous
temple district in Tokyo.)
ASC Arillaga Science Center, Building 057 (Formerly Photon Science Lab Building -- PSLB)
A-Scale Sound Level A measurement of sound approximating the sensitivity of the human ear, used to note the intensity or
annoyance of sounds.
ASCII American Standard Code for Information Interchange. Defines a 7-bit internal computer code for storing 128 letters,
numbers, punctuation, and
control codes. ASCII is used on almost all computers except some IBM mainframes (see EBCDIC). There is also an 'extended ASCII' which
provides for 256 characters.
ASCR Advanced Scientific Computing Research (DOE).
ASD Accelerator Systems Development / Department. (SSRL)
ASD Accelerator Systems Division.
ASE Accelerator Safety Envelope.
ASEB Aeronautics and Space Engineering Board.
ASER Annual Site Environmental Reports.
ASG Advanced Study Group (of the Max Planck Society).
ASGC Academia Sinica Grid Center.
ASHER Active Shooter/Hostile Event Response (NFPA Standard)
ASHRAE American Society of Heating, Refrigerating and Air-conditioning Engineers.
ASIC Application Specific Integrated Circuits.
ASLS Advanced Synchrotron Light Source.
ASME American Society of Mechanical Engineers.
ASO Accelerator Systems Operator.
ASOD Accelerator Safety and Operations division, Accelerator Directorate.
ASOS Absolute value Solid-On-Solid
ASP Astronomical Society of the Pacific.
ASPENS Astrometric Search for Planets Encircling Nearby Stars.
ASPERA AStroParticle European Research Area.
ASRF Accelerator Systems and Research Facilities. (SLAC)
ASRP Australian Synchrotron Research Program.
Assimilation The ability of a body of water to purify itself of pollutants.
ASST Accelerator Systems String Test
AST Above ground Storage Tank (ESH)
ASTA Accelerator Structure Test Area.
ASTB As Sent To Bidder.
ASTeC Accelerator Science and Technology Centre. (UK)
ASTM American Society for Testing and Materials.
ASTR Astronomy.
ASTRO-H The 6th Japanese-led international X-ray observatory, and the successor to the Suzaku satellite (ASTRO-E2)
Astronym ASTROnomical acroNYM
ASW Accelerator Safety Workshop.
Asymptotic freedom The decrease, at high energy, of the strong force between quarks.
Asynchronous Transmission by individual bytes, not related to specific timing on the transmitting end.
AT Ampere Trip.
ATA Allen Telescope Array.
ATA Activity Training and Authorization. When signed by the worker and their supervisor, this document authorizes and
releases a worker to perform activities in their resident area. It is valid for one year.
ATCA Australia Telescope Compact Array
ATCA Advanced Telecommunications Computing Architecture.
ATF Accelerator Test Facility / Advanced Test Facility.
ATF2 Accelerator Test Facility 2 (KEK).
ATHENA AnTiHydrogEN Apparatus (CERN).
ATLAS A Toroidal LHC ApparatuS. (A general purpose detector at the LHC at CERN).
ATM Asynchronous Transfer Mode
ATO Authority To Operate. (DOE)
ATOM Area Telecommunications Office Motivator
ATR Advanced microwave Technology Research department. (SLAC)
ATRAP Antihydrogen TRAP.
ATS Action Tracking System. (Replaced CATS)
ATSDR Agency for Toxic Substances and Disease Registry. (Federal)
ATST Advanced Technology Solar Telescope.
Attached Resource Computer Network See Arcane.
Attenuation The process by which a compound is reduced in concentration over time, through adsorption, degradation, dilution,
and/or transformation.
Attosecond One billionth of one billionth of a second.
AU Astronomical Units
AUI Associated Universities Incorporated
AURA Association of Universities for Research in Astronomy. It is an organization of various universities and other nonprofit
and educational institutions.
Auston switch Switch made of semiconductor material and triggered by an ultrafast optical laser. Passes an extremely short-lived
current when hit by a photon.
Authentication The process of identifying an individual, usually based on a username and password. In security systems, authentication
is distinct from authorization, which is the process of giving individuals access to system objects based on their identity. Authentication
merely ensures that the individual is who he or she claims to be, but says nothing about the access rights of the individual.
Autoignition Temperature The temperature at which a material (solid, liquid, or gas) will self-ignite and sustain combustion in
the absence of a spark or flame.
Auxiliary Door Any door between two PPS areas. An internal door in a PPS controlled zone.
AV Anti-Virus (Computing)
AVLIS Atomic Vapor Laser Isotope Separation
AWK Aho, Weinberger, and Kernighan. A Unix programming language for analyzing and manipulating text files.
AWLC Americas Workshop Linear Colliders
AXESS Stanford University employee benefits web portal.
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B The magnetic field of a Magnet. The physical symbol for magnetic field. The field in a magnet is sometimes referred to
as the `B-Field.'
B Bend magnet.
B Configuration See BCON.
B Requested See BREQ.
B&R Budget and Reporting. (sometimes listed as BNR)
B3 A bend magnet.
BA Breathing Apparatus.
BA Budget Authority.
BAAQMD Bay Area Air Quality Management District.
BAC Budget At Completion.
Back Phasing To change the position of a bunch with respect to the RF. This fixes wakefield effects where the energy of the
leading edge of the bunch is greater than that of the trailing edge.
Backbone The primary connectivity mechanism of a hierarchical distributed system. All systems which have connectivity
to an intermediate system on the backbone are assured of connectivity teach other. This does not prevent systems from setting
up private arrangements with each other to bypass the backbone for reasons of cost, performance, or security.
Background Refers to background noise, or to the spurious radiation in a detector that tends to obscure the data.
Backleg An extra winding on a magnet to add to, subtract from, or cancel a magnetic field. Sometimes called trim windings,
backleg windings `fine tune' adjustments to the field.
BACT Best Available Control Technology. (from CAA)
BACT The actual field of a magnet at the last computer check in kilogauss/meter for a quadrupole, in kilogauss for a bend.
BADC Brilliant ADC (Analog-to-Digital Converter)
Baikal an experiment in neutrino astronomy.
Bakeout The process of heating a vacuum pipe or chamber in order to drive out residual gas molecules which may have been
trapped in or on the cavity walls.
Bandwidth The capacity of the transmission medium stated in bits per second or as a frequency. The bandwidth of the
optical fiber is in the gigabit or billion bits per second range. Ethernet coaxial cable is in the megabit or million
bits per second range.
Banking A system for recording qualified air emission reductions for later use in bubble, offset, or netting
transactions. See also Emissions Trading.
BAO Baryon Acoustic Oscillations.
BAPVC Bay Area PhotoVoltaics Consortium.
Bar Screen In wastewater treatment, a device used to remove large solids.
Barn A unit of area equal to 10 to the minus 24 square centimeters, used to measure cross-sections in nuclear and
particle physics. The cross-section of a uranium nucleus is approximately one barn.
BARRnet Bay Area Regional Research Network. BARRnet was established in mid-1986 to serve the regional needs of
Northern California and surroundings as a mid-level component of the NSFnet and has been operational since May 1987.
The upper layer protocols in use are based on TCP/IP. SLAC connected to BARRnet through SUnet in the spring of 1988.
See also NSFnet and SUnet.
BART Best Available Retrofit Technology. (from CAA)
BAS Beam Analyzing Station. BAS-1 AND BAS-10 are magnetic spectrometers used to check beam energy and spectrum
(note that BAS-2 is no longer a spectrometer).
BAS Beam Authorization Sheet. An official document kept in the control room which lists all of the radiation
protection devices that must be locked in place to safely operate each beamline. Any changes to the BAS must be
noted and signed for by the Operator in charge. Signing the BAS document certifies that the EOIC has read and
understood all changes made to the current running conditions. Beams for each individual experiment are certified
by radiation physics and ADSO, and for each beam the BAS lists those devices of the BCS that must be checked by
the operator in charge before running that beam.
BAS Business Application Services. (SLAC)
BAS-1 Beam Analyzing Station-1. Located immediately following the chicane in sector 1.
BAS-10 Beam Analyzing Station-10. BAS-10 is located at the beginning of sector 10 in the LINAC. BAS-10 is used for
bunch length measurements: A dipole bends the beam to a screen and introduces dispersion. Bunch length is
transformed to an energy spread, which can then be measured accurately.
BAS-2 Beam Analyzing Station-2. The sector 20 dump is used to run the beam in a `LINAC only mode,' also called
BAS-2 MODE. Note that BAS-2 is no longer a Beam Analyzing Station. It is now a mode of operation that allows BSY
entry while the front two-thirds of the LINAC is on.
BAS-2 Mode BAS-2 was a beam analyzing station in sector 20 of the LINAC. BAS-2 mode is a LINAC mode of operation,
in which the beam is dumped in sector 20 dump. Because BAS-2 mode is not interlocked with the FF or the arc MPS,
operation may continue in BAS-2 mode whenever problems occur downstream of the BSY. The last two klystron sectors of
the LINAC, sector 29 and sector 30, are then routinely shut down as a PPS protection for entry into the BSY if necessary.
base A substance which forms a salt when reacted with an acid. Bases have a pH greater than 7.
Baseband Characteristic of any network technology that uses a single carrier frequency and requires all stations
attached to the network to participate in every transmission.
Basic User's Guide See BUG.
BASO Bay Area Site Office (DOE)
BASS Broadband Array Spectrograph System.
BAT Best Available Technology. (from CWA)
Batch Job A type of computer processing in which a batch of requests is stored and then executed all at one time. Batch job
processing can take place without the user being present or online.
Batch Queue A sequence of stored batch job requests that are awaiting execution.
Baud (rate) A unit of computer data transmission speed named after Emile Jean Baudot who developed a transmission system in 1874.
One Baud is equivalent to one BTS (BiT per Second).
Bay Area Regional Research Network See BARRnet.
BBA Beam-Based Alignment
BBN Big Bang Nucleosynthesis
BBR Black Body Radiation
BBS Behavior Based Safety.
BBU Beam BreakUp.
BC Bunch Compressor. (LCLS)
BC Bare Copper.
BCCB Baseline Change Control Board.
BCCP Berkeley Center for Cosmological Physics.
BCDR Business Continuity Disaster Recovery
BCIM Beam Current Intensity Monitor.
BCM Beam Containment Module.
BCON B CONfiguration. The B Field of a magnet as specified in a saved configuration. BCON can only be changed by loading
another configuration. Note that BDES changes to match BCON when a loaded configuration is activated.
BCP Business Continuity Plan.
BCP B physics and CP.
BCP Building Contact Person.
BCR Baseline Change Request.
BCS Beam Containment System. The beam containment system incorporates a variety of devices designed to prevent the beam
from damaging the machine or escaping into areas where it would represent a hazard to machinery and/or personnel. The system
uses comparators, average current monitors, SEM integrators, micro switches, flow switches, burn through monitors and
ionization chambers to detect excessive power being applied to the various machine parts that are in need of protection,
and to suppress the beam at its source (the injector) should this be necessary. Redundancy is liberally incorporated
into the beam containment system.
BCSOS Body Centered Solid-On-Solid
BCT Best Control Technology for conventional pollutants. (from CWA)
BCT Brady-Cerighton-Thorne
BCW Bare Copper Wire.
BCWP Budgeted Cost for Work Performed.
BCWS Budgeted Cost for Work Scheduled.
BD Beam Driven.
BDAT Best Demonstrated Available Technology. (from RCRA)
BDE Beam Dump East. The dump or area at the end of the A Line.
BDES B-DESired. The B field value of a magnet calculated from the model by the computer and saved into a configuration
by the operator. It is retrieved whenever the saved configuration is recalled. A magnet will be set to BDES value only
after the operator requests a trim action from the control system. BDES is usually calculated from the MODEL. BDES =
Rigidity factor X KMOD.
B-Desired See BDES.
BDL Beam Design Language. A stand-alone (non-SCP) program for setting TNOM for a given beam code.
BDMP Beam dump.
BDMPSZ Baier-Dokshitzer-Mueller-Peigne-Schiff-Zakharov
BDO Beamline Duty Operator for SSRL.
B-DOT The rate of change of a B field over time ( dB / dt ).
BDS Beam Delivery System.
BE Bose-Einstein
Beam Analyzing Station See BAS.
Beam Analyzing Station-1 See BAS-1.
Beam Analyzing Station-10 See BAS-10.
Beam Analyzing Station-2 See BAS-2.
Beam Authorization Sheet See BAS.
Beam Containment System see BCS.
Beam Design Language See BDL.
Beam Intensity Display See BIDB.
Beam Intensity Display Unit See BIDU.
Beam Position Monitor see BPM.
Beam Position Monitor Processor See BPMP.
Beam Position Monitor Stripline See BPMS.
Beam Shut Off Ion Chamber See BSOIC.
Beam Stay Clear See BSC.
Beam Switchyard See BSY.
Beam Tree Also sometimes called "current tree." A block of acrylic in which a defocussed
low-energy beam has been stopped. The block is then struck with a sharp metal object, and the
layer of additional charges is released as a cascade of current towards the point of impact. Permanent
damage to the acrylic caused by the current flow appears as a tree-like structure. Also called a
Lichtenberg tree. (For further information, see https://www.slac.stanford.edu/history/beamtree.shtml.)
Beamstrahlung The synchrotron radiation emitted by each bunch of particles as it passes through the
electromagnetic field of the opposing, or colliding bunch. Beamstrahlung signal is a function of the
luminosity at the interaction point.
Beamstrahlung Monitor See BSM.
Beamstrahlung Monitor Data See BSMD.
Beamtree See Beam Tree.
BEAP Building Emergency Action Plan.
BEARS Budget Execution And Reporting System (DOE)
BEAST Background Emission Anisotropy Scanning Telescope.
BEC "Bose-Einstein Condensate. A unique state of matter in which gas atoms, cooled to near-absolute-zero
temperatures, overlap with each other and collapse into a common quantum state, where they behave
essentially as a single "superparticle."
Becquerel The International System (SI) unit for activity of radioactive material. One becquerel is
that quantity of radioactive material in which one atom is transformed per second.
BELLA Berkeley Lab Laser Accelerator center.
Bend A dipole magnet.
Bend String Two or more bend magnets connected in series.
Bend Trim See BTRM.
BENE Beams for European Neutrino Experiments.
BENKEI KEK - PS detector
BEPC Beijing Electron Positron Collider
BEPC-II Beijing Electron Positron Collider upgrade (2006).
BER Biological and Environmental Research.
BES BEijing Spectrometer.
BES Basic Energy Sciences
BESAC Basic Energy Sciences Advisory Committee (DOE)
BESI Beam Energy Spectrum Indicator.
BES-III BEijing Spectrometer upgrade.
BESM Beam Energy Spread Monitor
BESS Breaking Electroweak Symmetry Strongly
BESSY "Berliner Elektronenspeicherring-gesellschaft für Synchrotron Strahlung."
Beta See Betatron Oscillation.
Beta Function See Betatron Oscillation. There is both a horizontal and a vertical beta function.
Beta Star The value of the beta function at the IP. There is a horizontal and a vertical beta star.
Betatron Oscillation The wavelength of the transverse oscillation of a beam, measured in meters. The
restoring force for the Betatron oscillations is provided by the quadrupole magnets which focus separately,
in the vertical and horizontal planes. Therefore, there are both horizontal and vertical betatron oscillations.
Beta is a Twiss parameter.
BeV Billion (Giga) electron Volt. This term was used in early writing about linear accelerators, but
GeV is now preferred. (See GeV)
Bezoic see BSOIC.
BF Batalin-Fradkin
BFACF Berg-Foerster-Aragao de Carvalho-Caracciolo-Frohlich
BFEM Balloon Flight Engineering Model.
BFFT Batalin-Fradkin-Fradkina-Tyutin
BFKL Balitskii-Fadin-Kuraev-Lipatov
BFL Beryllium Focusing Lens.
BFT Batalin-Fradkin-Tyutin
BFV Batalin-Fradkin-Vilkovisky
BFW Beam Finder Wire.
BFYM Balatin-Fradkin-Yang-Mills
BH Beam Hardener.
BH Black Hole
Bhabha An elastic electron-positron collision.
BHF Brueckner-Hartree-Fock
BHFP Black Hole Finder Probe.
BIA Business Impact Assessment.
BIC Bunch Intensity Control.
Bicep, Bicep2 Background Imaging of Cosmic Extragalactic Polarisation.
BICSI Building Industry Consulting Service International.
Big Science Science projects which have large budgets, many collaborators, and, more recently, are multinational.
BigBOSS Big Baryon Oscillation Spectroscopic Survey instrument.
Big-endian A format for storage or transmission of binary data in which the most significant bit or byte
comes first. The reverse convention is called little-endian.
Bill Of Lading A receipt listing goods shipped, issued by a common carrier.
Binder Service See Broker Service.
Binding Logically associating a name with a socket. When a handle for an ONC RPC is created, it is bound
to a network socket address.
Bino In models of supersymmetry, the lightest new particle and partner of the photon.
BINP Budker Institute for Nuclear Physics (Novosibirsk).
BIO Building Inspection Office (ES&H).
Bioaccumulation See Bioconcentration.
Bioconcentration A biological process whereby chemicals are accumulated in tissues at concentrations
above those in the immediate environment. This process is also knows as bioaccumulation.
Biodegradation The process of breaking down a chemical substance or mixture through biological mechanisms.
Biological Monitoring Use of biological organisms and their products to monitor toxicity levels.
Biological Treatment Treatment process utilizing living microorganisms to decompose organic wastes
into less complex organic or inorganic substances. Techniques include activated sludge, aerated lagoons,
trickling filters, waste stabilization ponds, and anaerobic digestion.
Biosecurity protocols and procedures to ensure infectious disease research is securely conducted,
e.g. pathogen control measures and monitoring to reduce biological risks
BIR Beam Interrupt Relay.
Bits per Second See BTS.
Bjorken scaling A method of predicting the behavior of inelastic electron scattering cross sections
developed by James D. Bjorken.
BKT Berezinskii-Kosterlitz-Thouless
BL Beam Line.
BL LACs BL LACertaes. A type of active galactic nuclei.
BLA Beam Line Authorization.
BlackHat Computer program that automates computation of QCD amplitudes.
BLD Beam Line Division
BLDG Building.
BLE Beam Line Electronics. (SSRL) PHOTON
BLEV E Boiling-Liquid-Expanding-Vapor Explosion. The possible result of a complex sequence of events involving
the impingement of flame on the exterior of a container of liquefied gas.
BLH Beam Line, Hard. LCLS Hard X-Ray beamline.
BLI Brightest Light Initiative
BLM Bureau of Land Management.
BLM Brodsky-Lepage-MacKenzie
BLR B-Layer Replacement. (ATLAS)
BLS Beam Line Systems. (SSRL)
BLT Batalin-Lavrov-Tyutin
BLT Back-Lit Thyratron.
Blue Book The popular name for the `The Stanford Two Mile Accelerator' by Richard B. Neal
(N.Y., Benjamin, 1968), SLAC Library call number QCD191.N41. Refers, too, to the 'SLC Design Handbook,' which also
has a blue cover. (Note that the paperback edition of 'The Stanford Two Mile Accelerator' is not blue.)
BM Building Manager. (SLAC)
BMAX The maximum allowable magnetic strength in kilogauss.
BMBF "BundesMinisterium für Bildung und Forschung. (The Federal Ministry of Education and Research)"
BMF Business Managers' Forum.(SLAC)
BMN Berenstein-Maldacena-Nastase
BMP Best Management Practices. (from CWA)
BMP Building Manager Program.
BMPF Best Management Practice Finding.
BMS Bondi-Metzner-Sachs.
BMSC Building Managers Steering Committee.
BMT Bargmann-Michel-Telegdi
BNCT Boron Neutron Capture Therapy
BNDS BeND String.
BNL Brookhaven National Laboratory, NY.
BNS Damping Balakin, Novakhatsky, and Smirnov are the names of the three Russian physicists who developed
the technique called BNS Damping. It is a technique which spreads the oscillation frequencies of the particles
in a beam (in order to avoid resonance) by introducing a longitudinal energy spread along the bunch. This is
done by backphasing early klystrons (creating an energy spread) and forward phasing later klystrons. Sometimes
inaccurately referred to as Landau Damping. See SLAC-PUB-3944.
BOD Basis of Design
BOC Business Offices Coordination meeting within the BTS organization for the Business and Finance
managers throughout the Lab (SLAC).
BOD Biochemical Oxygen Demand.
BOD Beam Overlap Diagnostic. A device used to locate the positions and orientation of the electron and x-ray
beams after they exit the magnetic chicane and grating monochromator. A subsystem of the Soft X-ray
Self Seeding (SXRSS) project.
BOD Bottom Of Duct.
Boiling Point See BP.
Boiling-Liquid-Expanding-Vapor Explosion See BLEVE.
Bone Yard A storage area north of Sectors 12 and 13 of the linac, where concrete blocks and metal scrap
used in radiation shielding applications are stored.
BOO Board Of Overseers. (Stanford)
bookmark (verb) To mark an electronic document or a specific place in an electronic document for later
retrieval. (noun) The hard-drive file that contains a URL and the text identifying the URL. Nearly all Web
browsers support a bookmarking feature that lets you save the address (URL) of a Web page so that you can
easily revisit the page at a later time.
BOOMERanG Balloon Observations Of Millimetric Extragalactic Radiation ANd Geophysics.
Booster to SPEAR See BTS.
BOOTP Bootstrap Protocol. An Internet protocol that enables a diskless workstation to discover its own IP
address, the IP address of a BOOTP server on the network, and a file to be loaded into memory to boot the
machine. This enables the workstation to boot without requiring a hard or floppy disk drive.
BOREXINO a solar neutrino experiment at the Laboratori Nazionali del Gran Sasso in Italy.
BOSS Baryon Oscillation Spectroscopic Survey. (Third Sloan Digital Sky Survey)
Bottomonium General name for the set of particles that contain both a bottom quark and an anti-bottom
quark, but are bound together with different energies.
Bounce The return of a piece of electronic mail because of an error in its delivery.
BP Boiling Point. The temperature at which a continuous flow of vapor bubbles occurs in a liquid being
heated in an open container.
BP Beam Physics.
BPE Borated PolyEster. Common term for specifically formulated polyester material used to shield gamma
and fast neutron radiation. Available in sheets, bricks, cylinders, blocks and in certain formulations, pellets.
BPFTW Braaten-Pisarski-Frenkel-Taylor-Wong
BPHZ Bogolyubov-Parasiuk-Hepp-Zimmerman
BPM Beam Position Monitor. A device including four electrodes located inside the beam pipe, and the
associated electronics necessary to locate the position of the centroid of the beam. The electrodes are
usually located about 90 degrees apart inside the vacuum chamber, far enough away from the beam's path
not to interfere with it, but close enough to feel the electric charge of the beam's passing.
BPM Strip One of four electrodes inserted in the beam line to measure the position of a beam. Also known as a Button.
BPMO See Beam Position Monitor.
BPMS Beam Position Monitor Stripline. Also used for BPM reading.
BPP Bose-Parker-Peleg
BPS Bits Per Second. The number of bits of data transferred by a terminal, modem, or computer in one second. See also Baud.
BPS Bogomolny-Prasad-Sommerfield
BPS Beijing Proton-Synchrotron.
BPT Best Practicable Technology. (from CWA)
BPWA Barrelet-zero Partial-Wave Analysis.
BPX Burning Plasma eXperiment.
BRAHMS Broad Range Hadron Magnetic Spectrometer, one of RHIC's detectors.
BRC Below Regulatory Concern.
BRDBD BReaDBoarD.
Breakthrough Time See BTT.
BREMSS BREMSStrahlung. (German: braking radiation)
Bremsstrahlung (German: braking radiation) The X rays emitted when a charged particle is decelerated by passing through matter.
BREQ B REQuested. The B field of a magnet asked for by a feedback process. BREQ is a magnet database secondary.
BRIDGE Bridging Research Interactions through collaborative Development Grants in Energy. (DOE)
BRM Business Relations Management.
Broadband "Characteristic of any network that multiplexes multiple, independent network carriers onto a single cable.
This is usually done using frequency division multiplexing. Broadband technology allows several networks to coexist on one
single cable traffic from one network does not interfere with traffic from another since the "conversations" happen on different
frequencies in the ether, rather like the commercial radio system.
Broker Service Synonymous with a binder service. It maintains binding information for network services.
Brown Out A reduced main line electric power condition caused by excessive draw on the power grid, usually due to a
combination of factors. These factors include irrigation pumps running in the San Joaquin Valley, air conditioners, wind
tunnel operation at NASA Ames Research Center, etc. When the brown out is imminent, SLAC usually gets enough notice to
shut down its major power-consuming devices to avoid excessively loading down the grid. We frequently get several hours
notice before a brown out, and can plan to run some of the lower power experiments on the site, depending on the maximum
power we are allowed to consume.
BRS Becchi-Rouet-Stora
BRST Becchi-Rouet-Stora Transformation. A quantization method of gauge and string theories.
BRZMNT BRaZeMeNT.
BS Bethe-Salpeter
BS Beam Stopper.
BSA Beam Synchronous Acquisition
BSC Beam Stay Clear. The maximum cross section a beam may have before particles get lost in the physical or dynamic
aperture, whichever is smaller. HEP
BSC BioSafety Cabinet (ES&H)
BSD "Berkeley Software Distribution. Term used when describing different versions of the Berkeley UNIX software,
as in ""4.3BSD UNIX.'"
BSE Bethe-Salpeter equations
BSFT Boundary String Field Theory.
BSI Broken Scale Invariant
BSL BioSafety Level
BSL-1 BioSafety Level 1, a basic level of containment that relies on standard microbiological practices (defined by the CDC).
BSM Business Service Management maps (ServiceNow).
BSOIC Beam Shut Off Ion Chamber. One of a number of PPS radiation-monitoring devices situated at strategic points throughout
the machine, usually close to, but on the outside of, the beam housing shielding. Ionization of the gas-filled chamber by
radiation will cause the BSOIC to trip off the beam if the level of radiation is above the trip point of the chamber. At SLAC
the BSOIC trip points are set at 100 mr/hour. The BSOICs are monitored both by MCC and OHP. They are fail-safe devices, and
will trip the beam off if unplugged. (Sometimes seen as BeSOIC or Bezoic).
BSRF Beijing Synchrotron Radiation Facility (China).
BSY Beam SwitchYard. The end of the LINAC where beams are switched to the SLC arcs, the PEP ring or end station areas.
BTCF Beijing Tau-Charm Factory (proposed)
BTEM Beam Test Engineering Model.
BTEM Beam TEst tracker Module (GLAST).
BTH Beam Transport Hall. (LCLS)
BTM Burn-Through Monitor.
BTO BaTiO3
BTP Biomedical Technology Program. (NIH)
BTP Batch Treatment Plant.
BTR Beam Target Room.
BTRM Bend TRiM. An extra winding of wire around the iron of a bend magnet designed for lower current, and with its
own power supply for independent control, used to fine adjust the field strength of the magnet. See Backleg.
BTS Booster To SPEAR. The beam transport line between the SSRL booster ring and the SPEAR storage ring incorporating
a section of the old 17 line.
BTS Base Transceiver Station (part of a cell phone tower).
BTT BreakThrough Time. The period of time that elapses between initial contact of one side of a protective barrier
(e.g. gloves, suits, etc.) and the time that the material is able to be detected on the other side of the barrier.
BTU British Thermal Unit.
BTUH British Thermal Units-Hours.
BTX Benzene-Toluene-Xylene.
BTZ Banados-Teitelboim-Zanelli
BU Bargaining Unit.
BU BackUp.
BU Business Unit.
Bucket One of the possible positions to store a bunch in a storage ring. The number of buckets can be calculated by
dividing the circulation frequency into the RF accelerating frequency. For example, if the RF oscillates 100 times
every time the bunch circulates once around the ring, then there are 100 buckets, or possible places for the bunch
to exist in that particular ring. In SPEAR, there are 280 possible buckets, and the users would like to be able to
fill all of them in order to maximize the stored current and the resultant synchrotron light.
Buffer A temporary storage facility, used to accumulate data into blocks of sufficient size to be handled
efficiently by a processor or terminal.
Buffer Zone An area of land which surrounds a hazardous waste facility and on which certain land uses and
activities are restricted to protect the public health and safety and the environment from existing or potential
hazards caused by the migration of hazardous waste. (CH&SE Sec. 251 10.3)
Bugger To jump or otherwise circumvent the interlocks in an operating system.
Bulk Supplies A power supply that feeds more than one magnet, usually by feeding unregulated DC power to more
than one regulator. In this manner, one large transformer and rectifier-filter system can feed several regulators,
which is usually cheaper than each magnet having its own complete power supply system.
Bunch A compressed packet of particles. A repeating train of such bunches is usually referred to as a beam.
Bunch Muncher A trigger driven device that momentarily shuts off the RF in the damping rings. In the past this
has been used to compress the bunch or to dump unwanted beams.
Buncher An accelerator section used to compress a cloud of electrons into a bunch.
Burn Through Monitor A beam containment device used to detect the destruction of a primary beam stopping device.
These units are usually canisters under pressure positioned near beam dumps or collimators. When the beam hits a
burn through monitor, the can develops a leak and the pressure drops. This pressure drop triggers a switch which
shuts off the accelerator. Formerly called Disaster Monitors or DM's.
Bus A collection of wires through which data is transmitted from one part of a computer to another.
Button See BPM Strip.
BUU Boltzmann-Uhling-Uhlenbeck
BV Balatin-Vilkovisky
BW Birman-Wenzl
BW BackWard.
BWM Birman-Wenzl-Murakami
BWR Boiling Water Reactor.
Back to top
C A high-level programming language developed by Dennis Ritchie and Brian Kernighan at Bell Labs in the mid
1970's. C is particularly popular with personal computer programmers because it is relatively small, and requires
less memory than other languages.
C&A Certification & Authorization.
C++ A high-level programming language developed by Bjarne Stroustrup at Bell Labs. C++ adds object-oriented
features to its predecessor, C. It is one of the most popular programming languages for graphical applications,
such as those that run in Windows and Macintosh environments.
CA Corrective Action (ES&H)
CA Channel Access
CA HSC CAlifornia Health and Safety Code.
CAA Clean Air Act. (42 U.S.C. Ch. 85, Sec. 7401 et seq)
Cable See CBL.
Cable Access Receiver See CAR.
Cable Access Transmitter See CAT.
CACM Contract Assurance / Contract Management.
CAD/CAM Computer Assisted Design / Computer Assisted Manufacturing.
CAE Chinese Academy of Engineering
CAER Community Awareness and Emergency Response (a CMA program).
CAIRS Computerized Accident / Incident Reporting System.
CAIs Calcium Aluminum-rich InclusionS.
CAL CALorimeter subsystem (GLAST).
CAL/OSHA California Occupational Safety and Health Administration.
Cal-ARP California Accidental Release Program.
Calendar Year See CY.
Calibration BPMs: Calibration measures pedestal and ADC linearity so the computer can position the beam
from the BPM data more precisely.
Calibration Magnets: A method of matching the actual current of a magnet to its set value. The DAC to
current function is accurately measured for improved trimming performance.
CALO Calorimeter.
Calorimeter A detector or any device measuring the energy of a particle or system.
CalSim CALibration SIMulation. (LSST)
CAM Control or Cost Account Manager.
CAM Continuous Air Monitor. (SSRL)
CAMEO Computer-Aided Management of Emergency Operations. (NOAA)
CAMERA Center for Advanced Mathematics for Energy Research Applications. (LBNL)
CAMP Capital Asset Management Process.
CAMP CFEL-ASG-Multi-Purpose. Instrument constructed for a series of exp eriments at the LCLS.
CAMS Corrective Action Management System.
CAMS Chemical and Materials Science (SSRL group)
CAN Controller Area Network.
CANDI Controller ANalog/Digital Interface card.
CANGAROO Collaboration of Australia and Nippon for a GAmma Ray Observatory in the Outback.
CAO Collaborative Agreement Order. Like a purchase order, but contain s a disclaimer that it is not
a contract, but is issued as an admi nistrative convenience.
CAP Continuous Acquisition Pixel.
CAP Corrective Action Plan
Cap Sigma Capital Sigma. The square root of the quadratic sum of the sizes of the two beams at the IP.
It is a fit parameter from a beam-beam deflection scan.
Capital Sigma See Cap Sigma.
CAPTAR The SLAC CAble Plant Tracking database.
CAPTCHA Completely Automated Public Turing test to tell Computers and Humans Apart.
CAR Canonical Anticommutation Relations
CARB California Air Resources Board. See ARB.
Carcinogenic Capable of causing cancer.
CARE Coordinated Accelerator Research in Europe.
CAS Cost Accounting Standards.
CAS Contract Assurance System.
CAS CERN Accelerator School.
CAS Chinese Academy of Sciences.
CAS Chemical Abstracts Service.
CAS Condition Assessment Surveys
CASA Center for Advanced Studies of Accelerators.
CASE Computer-Aided Software Engineering.
Cask A thick-walled container (usually lead) used to transport radioactive material. Also called a coffin.
CAST CERN Axion Solar Telescope.
CASTOR Centauro And Strange Object Research.
CAT Cherenkov Array at Themis. Astronomy telescope array in the French Pyrenees.
CatApp Computer application developed by SUNCAT scientists that displays reaction and activation energies for reactions
occurring on cataly tic metal surfaces.
CATER Comprehensive Accelerator Tool For Enhancing Reliability. Accelerator trouble reporting system.
Caustic Soda Sodium Hydroxide, a strong alkaline substance used as the cleaning agent in some detergents.
Caustics A large class of substances which form solutions having a high pH, also bases and alkalis.
Cavity A metal enclosure whose dimensions are designed to resonate at some given RF or microwave frequency. Used to
accelerate beams and/or compensate for loss of beam power in damping and storage rings.
Cavity resonator A tunable copper cavity capable of storing electromagnetic energy of a particular wavelength
and frequency and then, when properly synchronized, of imparting that energy to an electron beam passing through it.
Invented by William W. Hansen, who called it the rhumbatron.
CAYG Clean As You Go
CAZ Controlled Access Zone.
CBAR Contracts, Billing and Accounts Receivable (SLAC)
CBD Commerce Business Daily
CBF Correlated Basis Function
CBI Cosmic Background Imager.
CBI Critical Behaviors Inventory.
CBL CaBLe. Klystron summary display message indicating that the cable has a problem.
CBM Cloudy Bag Model
CBR Cosmic Background Radiation
CBRP Campus Building Renovation Project (SLAC)
CBT Computer-Based Training.
CBXFEL Cavity-Based XFEL
CC Citizen Committee
CC Configuration Control.
CCAST China Center of Advanced Science and Technology.
CCB Change Control Board.
CCCP Chemical Carcinogen Control Program. (SLAC)
CCD Charge-Coupled Device. A device wherein semiconductors are arranged so that the output
of one serves as the input of the next .
CCD Charge Control Device.
CCFM Ciafaloni-Catani-Fiorani-Marchesini
CCIN2P3 Computing Center of the National Institute of Nuclear Physics and Particle Physics. (2 N's and 3 P's)
CCIRDA Coordinating Committee for Informatics Research Development and Application (DOE)
CCITT Consultative Committee International Telephone and Telegraph. A unit of the International
Telecommunications Union (ITU) of the United Nations. It produces technical standards, known as
recommendations, for all internationally controlled aspects of analog and digital communications.
CCITT V.24 A set of data communications standards, similar to RS-232C, that calls out the signals
to use to connect digital equipment to make the equipment compatible.
CCJ RIKEN PHENIX Computing Center in Japan, a regional center.
CCLRC the Council for the Central Laboratory of the Research Councils in England.
CCM Channel-Cut Monochromator. Device that uses a pair of crystals to produce a monochromatic beam.
CCR California Code of Regulations (formerly California Administrative Code).
CCR Canonical Commutation Relations
CCS Carbon Capture and Storage.
CCSG Child Care Subsidy Grant. (Stanford)
CCST California Council on Science and Technology.
cctbx.xfel Computational Crystallography ToolboX for X-ray Free-Electron Lasers.
CCTV Closed Circuit TV
CCW Constituent Concentrations in Waste.
CCWE Constituent Concentrations in Waste Extract.
CD Controls Department.
CD Critical Decision.
CDC Central Drift Chamber. A part of a typical colliding beam detector used to track charged particle trajectories.
CDC Controlled Document Collection. (SLAC)
CDC Center for Disease Control. (Federal)
CDE calorimeter Crystal DEtector (GLAST).
CDF Collider detector at Fermilab
CDFA California Department of Food and Agriculture.
CDHS California Department of Health Services (aka DHS, DOHS, SDOHS).
CDM Cold Dark Matter
CDMS Controlled Document Management System. (SLAC)
CDMS Cryogenic Dark Matter Search.
CDO Chief Diversity Officer (SLAC)
CDO Controlled Document Owner. (SLAC)
CDR Conceptual Design Report
CDS Controls & Data Systems PHOTON
CDS Controlled Document Specialist. (SLAC)
CDW Charge Density Waves.
CEA Commissariat à l'énergie Atomique. (French Atomic Energy Commission)
CEB Causal Entropy Bound.
CEBAF The Newport News, VA Continuous Electron Beam Accelerator Facility was officially dedicated on 5-24-96,
at which time its parent lab was renamed the Jefferson National Accelerator Laboratory (JNAL). CEBAF is a JNAL
accelerator that uses radio-frequency cavities made of super-conducting materials to propel high-energy electrons
around a race-track shaped course.
CEC California Energy Commission.
CEDE Committed Effective Dose Equivalent.
CEF Conventional and Experimental Facilities. (Formerly SEM and EFD)
CELESTE a cosmic gamma-ray experiment.
Cell The smallest structural part of living matter capable of functioning as an independent unit.
Cell In solid waste disposal, a hole where waste is dumped, compacted, and covered with layers of dirt on a daily basis.
Cell A repetitive transport line unit in which the optics are such that beta out = beta in. Typical LINAC cells
are 24 meters long, except for sectors two through fours which are six to 12 meters long.
CELLS Consorci per a la constuccio, Equipament i explotacio del Laborato re de Llum de Sincrotro. (Spain)
CEM Cascade Exiton Model.
CEM Continuous Emission Monitoring.
CENIC Corporation for Education Network Initiatives in California.
Central Drift Chamber See CDC.
Central Lab Addition Building 084. Also known as Central Lab Annex. (SLAC)
Centrifugal Collector A mechanical system using centrifugal force to remove aerosols from a gas stream or water from sludge.
CEP Capitol Equipment Project.
CEPE-DOE office of Cost Estimating and Program Evaluation-Department of Energy.
CEPP Chemical Emergency Preparedness Program. (from EPA)
CEQ Council on Environmental Quality.
CEQA California Environmental Quality Act. (CPRC Sec. 21000 et seq)
CERCLA Comprehensive Environmental Response, Compensation and Liability Act. Also known as Superfund.
(42 U.S.C. Ch. 1, Subch. J, Part 300 et seq)
Cerenkov detector see Cherenkov detector.
CERFnet California Education and Research Federation Network.
CERN European Organization for Nuclear Research, Geneva, Switzerland. (in French: Organisation Europeenne pour
la Recherche Nucleaire). The acronym, still used, derives from the organization's original name: Centre Europeen
pour la Recherche Nucleair.
CERS California Environmental Reporting System
CERT Community Emergency Response Team (SLAC)
Certifiable Systems Computer and telecommunications systems that can be used for, or modified to be used for,
classified information.
Certified Hazardous Waste Specialist See CHWS.
CESER Cybersecurity, Energy Security and EMergency Response, Office of. (DOE)
Cesiate The process of coating a cathode with a cesium compound to decrease its work function and improve its electron
yield is called cesiation. The polarized light source used at CID in 1992 had its cathode cesiated once every several days.
CesrTA Cornell electron storage ring - Test Accelerator.
CF Core Function. ENVIRO
CF Conflat Flange.
CfA Center for Astrophysics (Harvard-Smithsonian).
CFCs Chlorofluorocarbons. A family of inert, nontoxic, and easily liquified chemicals used in refrigeration, air
conditioning, packaging, insulation, or as solvents and aerosol propellants. Because CFCs are not destroyed in the
lower atmosphere, they drift into the upper atmosphere, where their chlorine components destroy ozone.
CFEL Centre for Free-Electron Laser science.
CFI CAD Framework Initiative.
CFL Color Flavor Locked.
CFO Chief Financial Officer.
CFP Cosmology and Fundamental Physics.
CFR Code of Federal Regulations.
CFS Conventional Facilities and Siting. (Also shown as CF&S).
CFS Cubic Feet per Second.
CFT Conformal Field Theory
CG Center of Gravity
CGC California Government Code.
CG C Clebsch-Gordan coefficients
CGHS Callan-Giddings-Harvey-Strominger
CGI Combustible Gas Indicator.
CGI Common Graphical Interface
CGI Common Gateway Interface
CGM Computer Graphics Metafile.
CGR Carbon Glass Resistance
CGRaBS Candidate Gamma-Ray Blazar Survey project.
CGRO Compton Gamma Ray Observatory.
CGS Chemical and General Safety.
CH Combinatorial Hierarchy.
CH CHicago office. (DOE)
CH&SC California Health and Safety Code.
CHANDRA See CXO
ChEM-H Chemistry, Engineering, and Medicine for Human Health. (Stanford)
Chemical Emergency See Emergency (Chemical).
Chemical Transportation Emergency Center See CHEMTREC.
CHEMNET A mutual aid network of chemical shippers and contractors accessible
through CHEMTREC.
ChemRIXS Chemical RIXS
CHEMTREC CHEMical TRansportation Emergency Center. Sponsored by the Chemical Manufacturers Association.
Telephone: 800-424-9300.
CHEP Computing in High Energy and nuclear Physics (conference).
Cherenkov Detector A detector for counting or detecting high energy charged particles. The particle passes through
a liquid or a gas, and the light emitted as Cherenkov radiation is registered by a photomultiplier tube. (Cherenkov
radiation is produced when a charged particle passes through a medium at a speed greater than the speed of light
in that medium.)
Cherenkov Ring Imaging Detector See CRID.
CHESS Cornell High Energy Synchrotron Source.
CHFB Cranked Hartree-Fock-Bogoliubov
CHI CHIcane.
Chicane A Beam line bump made with four bend magnets. Chicanes are used as energy filters to transmit only the part
of the spectrum wanted or to eliminate particles of the wrong charge (as in the positron chicane in EP02). The
strengths of the four bends are calculated to transmit beams of a specific energy. There are three chicanes
in the SLC: the CID Compressor Chicane, the LI01 Chicane, and the EP02 Chicane.
CHICOS California High school Cosmic ray ObServatory.
CHIPP the Swiss Institute of Particle Physics.
Chirped Beam A beam that is accelerated so that the tail of the electronc bunch can be given a higher energy
than the head (LCLS).
CHL Chaudhuri-Hockney-Lykken
CHLOREP CHLOrine Emergency Plan operated by the Chlorine Institute and activated through CHEMTREC.
Chlorinated Hydrocarbons Halogenated hydrocarbons in which the halogen in the molecular structure is chlorine.
Chlorinated Solvent An organic solvent containing chlorine atoms, e.g., methylene chloride and 1,1,1-trichloralmethane
which is used in aerosol spray containers and in traffic paint.
Chlorofluorocarbons See CFCs.
CHP California Highway Patrol.
ChPT Chiral Perturbation Theory
CHRIS/HACS Chemical Hazard Response Information System/Hazard Assessment Computer System. Developed by and accessed
through the U.S. Coast Guard. Also available for purchase in four manuals. HACS is a computerized model of the four CHRIS manuals.
CHRO Chief Human Resources Officer (SLAC)
Chromatic Aberration The energy-dependent distortion caused by a quadrupole. Particles of different energy are focused
to different points because high-energy particles are focused (or bent) less than lower-energy particles. This is analogous
to light optics, where light of different colors has different wavelengths (energy) and therefore different indexes of
refraction when passing through a thin lens.
Chromatic Filamentation The increase in the phase space area resulting from chromatic aberration. As the beam rotates in
phase space, the resulting emittance is larger.
Chronic Effects Toxic effects which occur over relatively long periods of time, e.g., months or years. See also Acute Effects.
Chronic Toxicity A qualitative measure of a toxic agent administered repeatedly over a long period of time, e.g.,
months or years. See also Acute Toxicity.
CHSC California Health and Safety Code.
CHWMP County Hazardous Waste Management Plan. (CH&SC Sec. 25135 et seq)
CHWR CHilled Water Return.
CHWS Certified Hazardous Waste Specialist. A certification issued by the National Environmental Health Association (NEHA)
to degreed individuals with specified experience in hazardous waste management who pass a written examination.
CHWS CHilled Water Supply.
Ci Curie. A quantitative measure of radioactivity equal to 3.7 x 1010 disintegrations per second.
CICC Cable In Conduit Conductors
CICG Centre International de Conférences Genève. (Geneva International Conference Center)
CICHEP Cairo International Conference on High Energy Physics.
CID Center for Inverse Design. DOE National Renewable Energy Lab (NREL ) project in which SSRL is a participant.
CID Analyzing Station See CAS-0.
CIEMAT Centro de Investigaciónes Energéticas, Medioambientales y Tecnológicas. (Research Center for Energy, Environment and
Technology).(Spain)
CIFAR Canadian Institute For Advanced Research.
CIM Constituent Interchange Model.
CINVESTAV Centro de INVestigación y de ESTudios Avanzados del Instituto Politécnico Nacional. (Center for Investigation
and Advanced Studies of the National Polytechnic Institute in Mexico)
CIRCE The Coherent InfaRed CEnter, at LBNL.
CIS Commonwealth of Independent States.
CISAC Committee on International Security and Arms Control (National Academy of Sciences)
CISAC Center for International Security and Cooperation. (Stanford)
CISC Complex Instruction Set Computer.
CISC Center for Interface Science and Catalysis. (SLAC/Stanford)
CISE Computer and Information Science and Engineering
CISO Chief Information Security Officer.
CISTI Canada Institute for Scientific Technology Information.
CIT Compact Ignition Tokamak.
CITRIX Software application that allows SLAC staff and users to access computer accounts from home.
CIV Cachazo-Intriligator-Vafa.
CJT Cornwall-Jackiw-Tomboulis
CKM Cabibbo-Kobayashi-Maskawa. The name given to a matrix of numbers related to quark interactions. The numbers are
often shown in a gr aphical form called the unitary triangle.
CL Controller Laser.
CLAS CEBAF Large Acceptance Spectrometer
Class A Fires Fires involving ordinary combustible materials.
Class B Fires Fires involving flammable liquids.
Class C Fires Fires involving energized electrical equipment.
Class D Fires Fires involving combustible metals such as Li, Mg, Ti, Zn, Na, and K.
CLCWL China's Linear Collider Workshop.
CLE2 CLEO II detector at CESR.
CLEAN Continuous wave Linac for Efficiency and Availability iNnovation. -->
Clean Room A specifically prepared and designated location that limits the intrusion of airborne particles and/or
fume contamination using positive pressure, filtered air, special ventilation systems, and other methods.
Cleanup Actions taken to deal with a release or threat of release of a hazardous substance that could affect humans
and/or the environment. The term `cleanup' is sometimes used interchangeably with the terms remedial action, removal
action, response action, or corrective action.
CLGW CooLinG Water.
Client/Client Process A program running on a network workstation that requests services from a network server. For example,
a client might be a user sitting at a workstation using a front end program--a client process --that makes a request to a
database server for data.
Client-Server Architecture A distributed computing system in which a client process (a front end program requesting a service)
sends a request to a program running on another machine (a server) to perform some function. For example, a database client might
request a database server to supply some collection of sorted data. The server performs the sort and sends the sorted data to the client.
CLM Chemical Lifecycle Management (ESH)
CLNSF Collaboration of the Light-and Neutron-Source Facilities. (US)
CLOC Central Lab Office Complex. (LCLS)
Closed-Loop Recycling Reclaiming or reusing wastewater for non-potable purposes in an enclosed process.
CLR Common Language Runtime.
CLSS Compton Laser Safety Stopper.
CM Crisis Manager.
CM Construction Manager.
CM Center of Mass
CMA Chemical Manufacturers Association.
CMB Cosmic Microwave Background.
CMBR Cosmic Microwave Background Radiation.
CMB-S4 Cosmic Microwave Background-Stage 4
CMD Cryogenic magnetic detector at VEPP-2M, Novosibirsk.
CMDB Configuration Management DataBase (ServiceNow)
CMFD Centrally Managed - Field Deployed.
CMIP Common Management Information Protocol. An OSI standard protocol used with the Common Management Information Services (CMIS).
CMIS Common Management Information Services.
CMMS Computer Maintenance Management System.
CMOS Complimentary Metal-Oxide-Semiconductor detector.
CMR Colossal MagnetoResistance.
CMRF Cryomodule Maintenance and Repair Facility (SLAC)
CMS Compact Muon Solenoid, general purpose detector at the LHC (CERN).
CMS Chemical Management Services.
CMS Central Lab Machine Shop. A SLAC Group.
CMS Center-of-Mass System.
CMS Content Management Software.
CMSSM Constrained Minimal Supersymmetric Standard Model.
CMT Crisis Management Team.
CN Cyanide.
CNAO Centro Nazionale di Adroterapia Oncologica, located in Pavia in Italy.
CNGrid China National Grid.
CNGS CERN Neutrinos to Gran Sasso, a project.
CNLS Cornell Laboratory of Nuclear Studies.
CNM Chiral NonMinimal
CNN Convolutional Neural Network.
CNRS Centre National de la Recherche Scientifique (France).
CNS Central Nervous System.
CNTR Counters.
CO Conduit Only.
Coaxial Cable An electrical cable in which a piece of wire is surrounded by insulation and then surrounded by a tubular
piece of metal whose axis of curvature coincides with the center of the piece of wire, hence the term, `coaxial.' Such
cable offers high transmission rates, and is used by Ethernet.
COBE COsmic Background Explorer satellite.
COBIT Control Objectives for Information and Related Technology.
COD Chemical Oxygen Demand.
COE Conduct Of Engineering.
COFC Container On Flat Car.
COG Continuity Of Government.
COH1 and COH2 COHerent 1 and COHerent 2 lasers. Used as sources for the beam
CoHE Control of Hazardous Energy.
Coherent Oscillation An oscillation created when all particles of a bunch oscillate with the same phase.
COI Conflict Of Interest.
Coliform Index A rating of the purity of water based on a count of fecal bacteria.
COLIM COLlIMator.
Collaboration The set of physicists (and related postdoctoral and graduate students) who are actively involved in a
specific experiment at any time during its development, running, analysis and publication
Collider Injector Development See CID.
Collimator Sometimes called `slit.' A mechanical device installed in a beam line in order to reduce the aperture.
SLC collimators are either `fixed' or have movable `jaws' and are used to define the energy and/or remove beam tails.
Protection collimators are used to intercept high power beams before they can impact on magnetic elements in a beam
line. See also PC.
COLTRIMS COld Target Recoil Ion Momentum Spectroscopy
Combustion Product Substance produced during the burning or oxidation of a material.
COMET superconducting proton cyclotron at the Paul Scherrer Institute (P SI).
COMFORT A program to design transport line optics. COMFORT computes only twiss and storage ring parameters.
Command Post See CP.
Common Management Information Protocol See CMIP.
Community Antenna Television See CATV.
Community Toxicology Unit See COMTU.
COMPASS Common Muon and Proton Apparatus for Structure and Spectroscopy (CERN)
COMPLETE COordinated Molecular Probe Line Extinction Thermal Emission surve y.
Compliance Schedule A negotiated agreement between a pollution source and a government agency that specifies dates and
procedures by which a source will reduce emissions and, thereby, comply with a regulation.
Compressor A system, incorporating an RF source and a bending transport line section, used to reduce the length of a
particle bunch. An energy spread is introduced into the bunch using a short accelerator section. The leading particles,
with more energy, will traverse a longer path through the bend section because they bend less. The tail, or trailing
particles of lower energy, will make a sharper bend and catch up with the head, thus reducing the bunch length. This
method is used to reduce bunch length after the damping rings in the NRTL and the SRTL.
Compton Effect The reduction in the energy of high-energy photons when they are scattered by free electrons during
elastic collisions.
Compton Polarimeter A device which ascertains the degree of polarization of the electron beam by measuring the
cross section of compton-scattered electrons from polarized laser light.
Computer Architecture The area of computer study that deals with the physical structure (hardware) of computer
systems and the relationships among these various hardware components.
COMTU COMmunity Toxicology Unit. A subdivision of DHS.
Confined Aquifer See Artesian Aquifer.
Conservation Avoiding waste of, and renewing when possible, human and natural resources. The protection, improvement,
and use of natural resources according to principles that will assure their highest economic or social benefits.
Contaminant Any physical, chemical, biological, or radiological substance or matter that has an adverse
effect on air, water, or soil.
Contingency Plan A document setting out an organized, planned, and coordinated course of action to be followed
in case of a fire or explosion or a release of hazardous waste from a TSDF or a generator's facility that could threaten
human health or the environment. (from RCRA)
Control Technique Guidelines See CTG.
Controlled Access A PPS interlocked state that allows controlled entry without violating the `searched state' of
an SLC area. An MCC operator must visually (by remote cable TV) identify and log all persons entering or leaving the area.
An interlocked key bank system is used to control the number of people in the area. The operator logs the names of the
people entering the area, and releases each of them a key which they may use for entry and must return upon leaving the area.
Controlled Area An area wherein entry is controlled for the purpose of radiation protection.
CONTV CONTrol Valve.
COO Chief Operating Officer.
Cookie A message given to a Web browser by a Web server. The browser stores the message in a text file called cookie.txt.
The message is then sent back to the server each time the browser requests a page from the server.
Coolant A liquid or gas used to reduce the heat generated by power production in nuclear reactors, electric generators, various
industrial and mechanical processes, and automobile engines.
Cooling Tower A structure that helps remove heat from water used as a coolant, e.g., in electric power generating plants.
COPC Chemicals Of Potential Concern (ESH)
COPPER Modularized pipeline readout electronics system. Developed for KEK B-factory upgrade.
CORBA Common Object Request Broker Architecture, a software system which deals with distributed object computing
CORE Committee for Outreach, Recruitment & Engagement. (SLAC)
CORR CORRector magnet
Corrosion The dissolving and wearing away of metal caused by a chemical reaction such as between water and the pipes
that the water contacts, chemicals touching a metal surface, or contact between two metals.
Corrosive A chemical agent that reacts with the surface of a material causing it to deteriorate or wear away.
COSM Cosmology and astrophysics.
COSMOS COsmologically Significant Mass Oscillation Search (A Fermilab Exp eriment)
Cost Recovery A legal process by which potentially responsible parties who contributed to contamination at a Superfund
site can be required to reimburse the Trust Fund for money spent during any cleanup actions by the federal government.
CoSWMP County Solid Waste Management Plan. (California)
COSY COoler SYnchrotron.
COTR Coherent Optical Transition Radiation.
COTS Commercial Off The Shelf, components that are commercially available, generally in stock.
Counter An electronic device used to count pulses or the frequency of oscillations.
Counter A particle detector used for counting particles or monitoring radiation.
COUPP Chicagoland Observatory for Underground Particle Physics.
Cover Vegetation or other material providing protection as ground cover.
COVID-19 COronaVIrus Disease 2019 (previously known as "2019 novel coronavirus")
CP Cathodic Protection.
CP Command Post. A facility located at a safe distance upwind from an accident site, where the on-scene coordinator,
responders, and technical representatives can make response decisions, deploy manpower and equipment, maintain liaison with
news media, and handle communications.
CP Charge Parity.
CP Symmetry Charge-parity symmetry. Under this principle, the physics of an interaction would be unaffected if a
particle were to be converted into its anti-particle and viewed in a mirror.
CP Violation The small but important asymmetry of the weak interactions under the combined operations of charge
conjugation and parity inversion. Was discovered experimentally by James Cronin and Val Fitch of Princeton, who won the
1979 Nobel Prize in Physics for the discovery.
CPARS Contractor Performance Assessment Reporting System.
CPC Chemical Protective Clothing.
cPCI compact Peripheral Component Interface.
CPDG Comprehensive Project Design Guidance. (ILC)
CPE Controls and Power Electronics (Operations Directorate).
CPI Communications & Power Industries (Palo Alto)
CPIC Capital Planning and Investment Control.
CPIX Channeled-Proton-Induced Xrays.
CPO Chiral Primary Operator
CPP Compliance Partnership Program.
CPR CardoPulmonary Resuscitation
CPRC California Public Resources Code.
CPS Circular Polarization Sign.
CPSA Consumer Product Safety Act.
CPSC Consumer Product Safety Commission.
CPSR Contractor Purchasing System Review.
CPT Charge Parity Transformations
CPT theorem Charge conjugation Parity inversion Time reversal theorem. Holds that physics should not discriminate
between particles and anti-particles (moving backwards in time).
CPU Central Processing Unit (in a computer)
CPV Charge-Parity Violation.
CPWC Central Proportional Wire Chamber.
CQA Contractor and Quality Assucance office (SLAC)
CQM Constituent Quark Model
CR Cosmic Ray.
CRAC Computer Room Air Conditioners.
CRAD Criteria Review and Approach Document.
CRADA Cooperative Research and Development Agreement (between a DOE contractor and private industry)
Crash Bar A device to push open a locked PPS gate in case of a fire or other emergency. Crash bars can be reset
only with special keys kept in the MCC control room keysafe.
CREAM Cosmic Ray Energetics and Mass experiment.
CRENEL Commission to Review the Effectiveness of the National Energy Laboratories.
Criteria Descriptive factors taken into account by EPA in setting standards for various pollutants. These factors
are used to determine limits on allowable concentration levels, and to limit the number of violations per year. When
issued by EPA, the criteria provide guidance to the states on how to establish their standards.
Criteria Pollutants The 1970 amendments to the Clean Air Act required EPA to set National Ambient Air Quality
Standards for certain pollutants known to be hazardous to human health. EPA has identified and set standards to
protect human health and welfare for six pollutants: ozone, carbon monoxide, total suspended particulates, sulfur
dioxide, lead, and nitrogen oxide. The term, `criteria pollutants' derives from the requirement that EPA must describe
the characteristics and potential health and welfare effects of these pollutants. It is on the basis of these criteria
that standards are set or revised.
CRL Compound Refractive Lens.
CRM Customer Relations Management.
CRO Chief Research Officer.
CROP Cosmic Ray Observatory Project.
Cross Section A measure of the probability that a collision will occur between a beam and a particular particle. The
rate for a given process is proportional to its cross-section.
Cross Section The area of the section of an object generated by the intersection of a plane with that object.
Crowbar A circuit designed to quickly short out an electrical voltage in order to protect either equipment or personnel
downstream of the system.
CRPP Centre de Recherches en Physique des Plasmas.
CRSI Concrete Reinforcing Steel Institute.
CRT Cathode Ray Tube
CRYO CRYogenic Operations. A SLAC Group in the Experimental Facilities Department that is responsible for the storage,
transportation and use of low temperature liquid gases (commonly used as targets, or in detectors and superconducting magnets).
cryo-EM cryo-Electron Microscopy
cryo-ET cryo-Electron Tomography
Cryo-FIB-SEM Cryo-Focused Ion Beam- Scanning Electron Microscopy
Cryo-FIB-TEM Cryo-Focused Ion Beam-Transmission Electron Microscope
cryoFLM cryo-Fluorescence Light Microscopy
Cryogenic Substance having a temperature below -150 degrees F (-101.1 degrees C).
Cryogenic Operations See CRYO.
Cryogenics The branch of physics and engineering dealing with very low temperatures.
Cryogenics Engineering See CYE.
Cryostat An apparatus for maintaining a very low temperature. The final focus superconducting triplet quadrupoles
and the spin rotator solenoids are enclosed in cryostats (a fancy name for a thermos bottle).
CSA Canadian Standards Act.
CSA Chemical Waste Storage Area.
CSB Charge Symmetry Breaking.
CSB2 Columbia University - Stony Brook GBO calorimeter installed in an NaI array.
CS C Cathode Strip Chambers.
CSCNS Committee on Scientific Communication and National Security (NAS)
CSGAC Chinese Scientists Group on Arms Control
CSGB Chemical Sciences, Geosciences, and Biosciences Division (DOE)
CSIP Charge-Sensitive Infrared Phototransistor.
CSIP Cyber Safety Improvement Plan / Program.
CSIRO Commonwealth Scientific and Industrial Research Organisation. (Australia)
CSIS Center for Strategic & International Studies (Washington D.C.)
CSKR Cremmer-Scherk-Kalb-Ramond.
CSM Calogero-Sutherland-Moser
CSO Caltech Submillimeter Observatory (Hawaii).
CSO Chief Safety Officer. (SLAC)
CSP Chemical Strategies Partnership.
CSPP Cyber Security Program Plan.
CSR Coherent Synchrotron Radiation.
CSS Common Site Support
CSX Five channel differential transceiver.
CT Computer-assisted Tomography.
CT Cooling Tower.
CT Cold Test.
CTA Cerenkov Telescope Array.
CTBT Comprehensive Nuclear Test-Ban Treaty
CTC Closed Timelike Curves.
CTD Cumulative Trauma Disorder. A form of musculo-skeletal disorder caused by damage to tissue from repetitive
motion or sustained posture.
CTEQ Coordinated Theoretical-Experiment project on the QCD.
CTF Collider Test Facility
CTG Control Technique Guidelines. A series of EPA documents designed to assist states in defining reasonable
available control technology (RACT) for major sources of volatile organic compounds (VOC).
CTM Corner Transfer Matrix
CTP Closed Time Path
CTW Cooling Tower Water.
CUDA Compute Unified Device Architecture. An open-source compiler.
CUI Controlled Unclassified Information.
CUIR Critical Utility Infrastructure Revitalization (DOE)
Cumulative Working Level Months See CWLM.
CUORE Cryogenic Underground Observatory for Rare Events. (Italy)
CUP Central Utility Plant.
Curie See Ci. ENVIRO
CUSB Columbia University-Stony Brook segmented NaI detector at CESR.
CV Cost Variance.
CVD Chemical Vapor Deposition method
CVM Cluster Variation Method
CVP Central Valley Project (WAPA_CA)
CVSS Common Vulnerability Scoring System. (Computing)
CW Code Workshop.
CW Continuous Wave (RF).
CW Cooling water. See also LCW.
CWA Clean Water Act. (33 U.S.C. Sec. 1251 et seq)
CWC California Water Code.
CWE Current Working Estimate.
CWFA Cherenkov Wake Field Accelerator
CWKB Gomplex Wentzel-Karmers-Brillouin.
CWLM Cumulative Working Level Months. The sum of lifetime exposure to radon working levels expressed
in total working level months.
CWMA Centralized Waste Management Area.
CWMB California Waste Management Board.
CWR Contingent WorkeR.
CX Categorical Exclusion.
CXD Categorical Exclusion Determination.
CXI Coherent X-ray Imaging (LCLS).
CXIDB Coherent X-ray Imaging Database.
CXL The central controller chassis from Cerberus, used at SLAC for fire detection.
CXO Chandra X-ray Observatory
CY Calendar Year, 1 Jan thru 31 Dec. See also FY (Fiscal Year).
CY Calabi-Yan
Cyberspace A term coined by William Gibson in his fantasy novel `Neuromancer' to describe the `world' of computers,
and the society that gathers around them. Now more generally defined as the on-line world of computer networks.
CYE CrYogenics Engineering. A SLAC Organizational Group.
CYL CYLinder.
CYO CrYogenics Operations.
Czar Term used to designate person within a group who has responsibility for administration of a type
of information resource. See also mega-czar.
Back to top
D Usually refers to a beam dump. ALSO: D.
D Dipole magnet.
D Wastes A federal waste category for those wastes which exceed maximum concentrations of toxic
components based on the EP Toxicity test.
D&D Decontamination and Decomissioning
D0 FNAL-COLLIDER detector (D-Zero).
DAB Data Assembly Building. Now called the Main Control Center (MCC).
DAC Digital to Analog Converter. Usually used to control a power supply.
DAC Director's Assurance Council. (SLAC, 2011- )
DACT Direct ACTion.
Daemon A server or process running on a server that lies dormant until called upon to perform a
service. Most servers are daemons.
DAMA particle DArk MAtter search. (INFN)
DAMA/LIBRA particle DArk MAtter search using Large sodium Iodide Bulk for RAr e processes.
DAMIC DArk Matter In CCDs. (Fermilab)
Damping Ring A system to reduce the transverse emittance of a beam. In a ring, accelerated
particles lose energy due to synchrotron radiation. In a damping ring, the lost energy is partially replaced
by an RF source, which boosts the parallel (or longitudinal) energy, but does not correct the damping of the
transverse emittance.
DAQ Data AcQuisition system.
Dark Current Spurious emission of electrons from a gun cathode or vacuum chamber wall in the
presence of high voltage or RF. Dark current can be picked up and accelerated by RF stations out of
phase with the main bunch.
DARPA Defense Advanced Research Projects Agency.
DART Days Away, Restricted, or Transferred. A subset of the Total Recordable
Case (TRC) rate.
DASEL DArk Sector Experiments at LCLS-II
DASI Degree Angular Scale Interferometer.
Data Compression A technique used for cutting transmission costs or time, or for saving
buffer space. It removes unnecessary gaps, redundancies, and empty fields from data streams.
Database See DB.
Database Executive See DBEX.
Database Generation See DBGEN.
Database Server A computer running a back-end (or server-based) database management program.
The database server performs all database functions (for example, retrieving and sorting data) for clients requesting
services.
Database/Database Management System "A collection of information organized in such a way
that a computer program can quickly select desired pieces of data a program specifically designed to
manage data.
Dataphones Service mark of the American Telephone and Telegraph Company for various
hardware products.
Dazzler See AOPDF entry.
DB Database. A collection of information organized in such a way that a computer program can quickly
select desired pieces of data.
DB Decibel.
DBA DataBase Administrator
DBD Detailed Baseline Design. (ILC)
DBHF Dirac-Bruckner-Hartreel-Fock
DBI Dirac-Born-Infeld
DBM Determined By Management.
D-brane In string theory, a ten-dimensional membrane that provides an anchoring
surface for strings. D-branes can have mass, momentum and charge, and are quantum versions of objects that
were first found as solitonic solutions of supergravity.
DC Data Challenges (GLAST simulations).
DC Drift Chamber.
DC Data Center.
DC1 Data Challenge 1. (GLAST)
DC2 Data Challenge 2. (GLAST)
DCAA Defense Contract Audit Agency.
DCB Design Cost Board. (ILC)
DCBA Drift Chamber Beta-Ray Analyzer
DCBD DC Bending Dipole.
DCC Disoriented Chiral Condensate
DCC Directorate Conference Coordinator.
DCCT Direct Current Current Transformer. A system used in storage rings to measure the stored current. It uses a toroid
and an integrator. PHYSICS
DCE Distributed Computing Environment. An architecture of standard programming interfaces, conventions, and server
functionalities for distributing applications transparently across networks of heterogeneous computers. Promoted and
controlled by the Open Software Foundation (OSF).
DCIM Data Center Information Management.
DCO Document Change Order
DCR Detector Concepts Report. (ILC)
DCS Design and Construction Services. F&O department/group at SLAC.
DCS Distributed Control System.
DDAA Decade of Discovery in Astronomy and Astrophysics.
DDC Digital Down Converter.
DDCCT A Device which measures and reads out the rate of change of the DC Current Transformer (DCCT). It is used to find the
fill/loss rate of current in storage rings.
DDE Dynamic Data Exchange. A protocol supported by Microsoft Windows that allows cooperating Windows applications
(applications that use the DDE specification) to establish both data and command links, which allow these cooperating
applications to exchange data in real time, initiate new processes and support compound documents that consist of elements
drawn from disparate files that are automatically updated as data changes in the external files.
DDO Deputy Director for Operations (SLAC)
DDP&I Deputy Director for Projects and Infrastructure
DDS&T Deputy Director of Science & Technology (SLAC)
DE Dark Energy.
DEAR Department of Energy Acquisition Regulations.
DECam Dark Energy survey Camera. (Chile-2012)
Dechlorination Removal of chlorine from a substance by chemically replacing it with hydrogen or hydroxide ions in order
to detoxify the substances involved.
DEEP Deep Extragalactic Evolutionary Probe.
Deep Well Injection The disposal of wastes by injecting them into a geological formation deep in the ground, sometimes
after pretreatment to avoid solidification.
Degaussing The process of removing the residual field in the iron of an electromagnet by reversing the polarity of the
power supply feeding that magnet, and putting just the right amount of power through the windings in the opposite direction.
This type of hysteresis neutralization is used when the operating field of the magnet must be precisely controlled.
Degradation The process by which a chemical is reduced to a less complex form.
DEI Diversity, Equity, and Inclusion
DEIMOS Deep Imaging Multi-Object Spectrograph.
DEIS Draft Environmental Impact Statement.
Delegated State A state (or other governmental entity) which has applied for and received authority to administer, within
its territory, its state regulatory program as the federal program required under a particular federal statute. As used in
connection with NPDES, UIC, and PWS programs, the term does not connote any transfer of federal authority to a state.
Delist The use of the petition process to have a facility's toxic designation rescinded.
DEMO DEMOnstration power plant (ITER).
DEMON A Monte Carlo program for electron-down quark (e-d) scattering.
DEMTBL DEMounTaBLe.
DENIS DEep Near Infrared Survey of the southern sky
Density Mass per unit of volume, commonly expressed in grams per cubic centimeter (g/cc). The density of water is 1.00 g/cc.
DEO Director of Emergency Operations.
DEOIC Deputy Engineering Operator In Charge.
DEPFET DEpleted P-channel Field Effect Transistor detector.
DEPFET DEpleted P-channel Field Effect Transistor. Pixel detector developed at MPI Halbeiterlabor Munchen.
DES Dark Energy Survey.
DESC Dark Energy Science Collaboration.
DESI Dark Energy Spectroscopic Instrument.
Designer Bugs Popular term for microbes developed through biotechnology that can degrade specific toxic chemicals at
their source in toxic waste dumps or in ground water.
DESTINY Dark Energy Space Telescope
DESY Deutsches Elektronen-SYnchrotron (Hamburg, Germany)
DESY PETRA DESY Positronen Elektronen Tandem Ring Accelerator (1978-1986), now PETRA III.
DETF Dark Energy Task Force. (HEPAP)
Deuce, The LCLS II.
DFA Department of Food and Agriculture. (California)
DFG Deutsche ForschungsGemeinschaft. (German Research Foundation)
DFMEA Design Failure Modes and Effects Analysis
DFR Doplicher-Fredenhagen-Roberts.
DFS "Distributed File System. A major component of DCE. It is OSF's extended version of the Andrew File System (AFS)
from Transarc. DFS is interoperable with other file systems. ""cd/:"" changes you to the directory at the top of your
cell ""cd/..."" changes you to the global root."
DFT Density Functional Theory.
DGLAP Dokshitser-Gribov-Lipatov-Altarelli-Parisi
DGP Dvali-Gabadadze-Porrati.
DGW Discharge to Ground Water.
DH Department Head.
DHCAL Digital Hadron Calorimeter. (ILC)
DHCP Dynamic Host Configuration Protocol. An Internet protocol for automating the configuration of
computers that use TCP/IP.
DHGHY Drell-Hearn-Gerasimov-Hosoda-Yamamoto.
DHGI Drell Hearn Gerasimov Iddings sum rule
DHHS Department of Health and Human Services. (federal)
DHS Department of Health Services (California, aka CDHS, SDOHS, DOHS).
DIAMOND Third-generation synchrotron radiation source in the UK.
DIANA DIagram ANAlyser
DIC Deep Inelastic Collisions
Diffraction elastic-like scattering
DigiSim Tool for fast parametric simulations of detector phenomena. (ILC)
Digital Any system based on discontinuous data or events. Computers are digital machines because at their most basic level they can
distinguish between just two values, 0 and 1, or off and on.
Digitizer Any analog to digital converter. See also ADC.
Digitizer A device used to digitize the light intensity created when a profile monitor is inserted in a beam transport line.
DIMAD A computer program used to study particle behavior in circular machines and in beam lines
Dioxin Any of a family of compounds known chemically as dibenzo-p-dioxins. Concern about them arises from their potential toxicity
and contamination in commercial products. Tests on laboratory animals indicate that it is one of the more toxic manufactured chemicals known.
DIP Distributed Ion Pump. Pumps that are integrated in the physical structure of dipole magnets, and use the dipole's magnetic
field to steer the ions into a 'trap.'
Dipole A magnet with a North and South pole, typically used to bend or steer a beam.
DIR Department of Industrial Relations. (California)
Direct Current Current Transformer See DCCT.
Directory Services A network function providing resource (file, user, printer, applications) information to end users.
DIRT Dust InfraRed Toolbox.
DIS Deep Inelastic Scattering
Disassembling Converting a binary program into human-readable machine language code.
Disc Loaded WaveGuide See DLWG.
Dispersion The blow up of a beam caused by an energy spread. The dispersion occurs when the beam is bent by a dipole magnet,
because charged particles with less energy bend more and particles with more energy bend less. See also ETA function.
Distributed Computing Environment A comprehensive programming toolkit that includes libraries for remote procedure calls,
network communication, and resource-management tools for the network, as well as tools for creating distributed applications.
Distributed File System A file system in which different pieces of files are contained in multiple file servers in multiple
locations throughout a given network. The system maintains all storage information, and ensures that a distributed file appears
transparently to the user as one single and whole file.
Distributed Ion Pump See DIP.
Distributed Processing An architecture under which different processes of a unique task are performed in multiple locations
of a given network. For example, data requested by a client might be retrieved from a database residing on a centralized mainframe,
sent to and sorted by a regional minicomputer, and finally returned to the workstation or possibly printed at the workstation's
local printer facility.
Dithers The last x, y correctors in the machine, just before the final triplets. They are air core dipoles which have a fast
response time and are used for beam scans and IP wire scans.
Divergence The increase in the diameter of a beam as a function of z position.
Divide By Four Any circuit which divides a frequency (or other parameter) by four.
DKFZ Deutsches KresForschungsZentrum, a German cancer research center.
DKP Dispersionless Kadomtsev-Petviashvili.
DL Dog-Leg beam position monitor. (LCLS)
DLA Direct or Delectric Laser Acceleration.
DLA Double Logarithmic Approximation
DLCQ Discretized Light Cone Quantization
DLDS Delay Line Distribution System.
DLHC Double energy Large Hadron Collider.
DLLA Double Leading Logarithmic Approximation
DLP Data Loss Prevention. (Symantec)
DLS Desktops & Labs Services (Computing)
DLSO Deputy Laser Saftey Officer.
DLWG Disc Loaded Wave Guide. The LINAC accelerator pipe is a Disc Loaded Wave Guide.
DM Deferred Maintenance.
DMA Direct Memory Access.
DMAIC Define, Measure, Analyze, Improve and Control.
DMAT Disaster Medical Assistance Team.
DMF Detector Microfabrication Facility. New state-of-the-art cleanroom in ASC for superconducting circuit fabrication (SLAC)
DMP Data Management Plan.
DMR Discharge Monitoring Report (from CWA).
DMR Differential Microwave Radiometers
DMS see CDMS.
DMSAG Dark Matter Scientific Assessment Group.
DMUF Dust Mask User's Form.
DMWG Data Management Working Group (SD&H).
DNA DeoxyriboNucleic Acid ENVIRO
DNF Disjunctive Normal Form
DNLS Discrete NonLinear Schrodinger
DNS Domain Name System. The method used to convert Internet names to their corresponding Internet numbers.
DNSTR DowN STReam.
DO Dissolved Oxygen.
DO Director's Office.
DOD Department Of Defense. (federal)
Dodecapole A twelve-pole magnet.
DOE Department Of Energy. Supercedes ERDA and the AEC. Established 4 August 1977.
DOE HQ DOE HeadQuarters (Washington, DC).
DOE/ORO Department of Energy Oak Ridge Operations office.
DOELAP DOE Laboratory Accreditation Program.
DOF Degree-Of-Freedom.
DOHS Department of Health Services (California, aka CDHS, DHS, SDOHS).
DOI Digital Object Identifier.
DOM Digital Optical Modules
Domain In the Internet, a part of the naming hierarchy. Syntactically, an Internet domain name consists of a sequence
of names separated by dots, for example slac.stanford.edu.
Domain Name System See DNS.
Dose In radiology, the quantity of energy or radiation absorbed.
Dose-Response Curve The quantitative relationship between the dose of a toxic agent administered to an organism
and the response of the organism.
Dosimeter An instrument to measure integrated radiation dose. See also TLD.
DOT United States Department of Transportation.
Dotted Decimal Notation The syntactic representation for a 32-bit integer that consists of four 8-bit numbers written
in base 10 with dots separating them. Used to represent IP addresses in the Internet as in: 192.67.67.20.
Dotted Quad A set of four numbers connected with periods that make up an Internet address, for
example: 147.31.254.130.
DPB Division of Particles and Beams (American Physicsl Society).
DPDF Diffractive Parton Distribution Functions.
DPE Dual-Phase Extraction (ESH)
DPF Division of Particles and Fields (American Physical Society)
DPHEP Data Preservation in High Energy Physics. An international collaboration of organizations for data preservation
and long term analysis.
DPLTA Data Preservation and Long-Term Analysis. (HEP)
DPO Differing Professional Opinions program (DOE)
DPWA Energy-Dependent Partial-Wave Analysis.
DQC Dynamic Quantum Clustering.
DR Damping Ring. ENGINEERING
DR Disaster Recovery.
DRA Data Risk Assessment (Stanford)
DRE Destruction and Removal Efficiency.
DREAM Dynamic REAction Microscope (or Microscopy)
DREP Dosimetry and Radiological Environmental Protection.
DRG Divisional Response Group.
Drift Chamber A particle detector that determines the track path of a particle by measuring the drift time for free
electrons from ionized gas along the particle's trajectory.
Driver A software module that controls an input/output port or external device. PC/TCP uses a device driver
to control the network interfaces.
DRP Data Reduction Pipeline
DS Direct Supervisor.
DS Desktop Support.
DS Dyson-Schwinger
DSE Dyson-Schwinger equations
DSES Dyson-Schwinger Equation Studies.
DSph dwarf Spheroidal (galaxies).
DSR Data Set Ready.
DSR Doubly Special Relativity.
DSS Decision Support Services.
DST Daylight-Savings Time.
DST Data Summary Tapes.
DSW Discharge to Surface Water.
DT Drift Tube.
DT Dynamically Triangulated
D-T Deuterium-Tritium.
DTC Drift-Tube Chambers.
DTD Document Type Definition (as for SGML)
DTM Data Transfer Module.
DTN Data Transfer Node
DTR Data Terminal Ready.
DTW Domestic Treatment Works.
Dump A device to absorb the full power of a beam, either while tuning or after it has been used by an experiment.
DUNE Deep Underground Neutrino Experiment.
DUPCD Device Using Pulse Control Devices.
Dust Particles light enough to be suspended in air.
Dustfall Jar An open container used to collect large particles from the air for measurement and analysis.
DVCS Deeply Virtual Compton Scattering
DVM Digital Volt Meter.
DW Data Warehouse.
DWA Dielectric Wakefield Accelerator.
DWBA Distorted Wave Born Approximation.
DWFA Dielectric WakeField Accelerator.
DWIA Distorted Wave Impulse Approximation.
DXS Dynamic X-ray Scattering instrument features two major experimental programs:
Inelastic X-ray Scattering and X-ray Photon Correlation Spectroscopy (LCLS-II HE)
Dynamic Data Exchange See DDE.
DYWIDAG DYckerhoff & WIDman AG. Company that manufactures post-tensioning and geotechnical construction systems.
DZM Darbourx-Zakharov-Manakov.
Back to top
E Experiment.
EA Enterprise Architecture.
EA Environmental Assessment.
EA Office of Enterprise Assessments. (DOE)
EAC Estimate At Completion.
EACT The energy in GeV for a quad strength as computed by LEM. It is based on data from klystron Enoload. See also ENLD.
EAPR Enterprise Architecture Project Review
EARN The European Academic Research Network. Started in 1983, EARN was the first and largest network serving academic
and research institutions in Europe, the Middle East and Africa. Initially begun with help from IBM, it evolved to become
a non-profit, non- commercial traffic-based network serving academic and research institutions.
EAS Extensive Air Shower
East Turn Around See ETA.
EBCCD Electron-Bombarded CCD
EBCDIC Extended Binary Coded Decimal Interchange Code. An 8-bit code for defining 256 different characters used on many
IBM main frame computers. See also ASCII.
EBD-FEE Electron Beam Dump - Front End Enclosure. single zone furthest downstream accelerator area
EBI Energy Biosciences Institute.
EBK Einstein-Brillouin-Keller
EBL Extragalactic Background Light.
EBT Extended Business Team.
EC European Commission.
EC Executive Committee. (ILC)
ECal Elctromagnetic Calorimeter. (ILC)
ECCO Eikonal Cascade COde
ECFA European Committee on Future Accelerators
ECI Electron Cloud Instability.
ECM Enterprise Content Management. Strategies and tools used to capture, manage, store, preserve, and deliver content
and documents related to organizational processes. ECM tools and strategies allow the management of an organization's
unstructured information, wherever that information exists.
Ecology The relationship of living things to one another and their environment, or the study of such relationships.
eConf Electronic Conference proceedings archive. ( http://www.slac.stanford.edu/econf/)
ECP Employee Concerns Program (DOE)
ECP Exposure Control Plan.
ECP Exascale Computing Project.
ECR Electron Cyclotron Resonance
ECSC Enterprise Computing Steering Committee.
ECSK Einstein-Cartan-Sciama-Kibble.
ED ElectroDialysis.
ED Engineering Design (ILC).
ED & M Electrical Development and Maintenance group, a department. (SSRL)
EDF Environmental Defense Fund.
EDG European DataGrid.
EDIA Engineering Design Inspection Acceptance (cost estimates).
EDM Electric Discharge Machining.
EDM Electric Dipole Moment
EDM Extensible Display Manager
EDMS Electronic Document Management System.
EDMS Engineering Data Management System (ILC).
EDR Engineering Design Report. (ILC)
EDS Electronics Drafting Shop.
EDS Engineering Demonstration System (LLNL)
EE EmployeE.
EE Electronics Engineering. Division of the SLAC Accelerator Directorate.
EED Electronics Engineering Division. (SLAC)
EEF Environmental Evaluation Form.
EEHG Echo-Enabled Harmonic Generation.
EEIP Electrical Equipment Inspection Program (SLAC).
EELA E-infrastructure shared between Europe and Latin America.
E-ELT European-Extremely Large Telescope.
EEOICPA Energy Employees Occupational Illness Compensation Program Act.
EEP Emergency Evacuation Plan.
EEQT Event Enhanced Quantum Theory
EERE Energy Efficiency and Renewable Energy. (DOE Office of)
EEW Energized Electrical Work request and approval permit.
EFE Einstein Field Equation-type.
Effluent Wastewater--treated or untreated--that flows out of a treatment plant, sewer, or industrial outfall. Generally
refers to wastes discharged into surface waters.
Effluent Limitation Restrictions established by a State or EPA on quantities, rates, and concentrations in wastewater discharges.
EFMEA External Failure Modes and Effects Analysis
EFRC Energy Frontier Research Center. (DOE)
EFT Effective Field Theory.
EGEE Enabling Grids for E-sciencE. (Consortium)
EGP Exterior Gateway Protocol. The protocol used by a gateway in one autonomous system to advertise the Internet addresses
of networks in that autonomous system to a gateway in another autonomous system. Every autonomous system must use EGP to
advertise network reachability to the core gateway system.
EGS Electron-Gamma Shower. A system of computer codes for Monte Carlo simulation of the coupled transport of electrons
and photons in an arbitrary geometry for particles with energies ranging from above a few keV up to several TeV.
EGS Ehlers-Geren-Sachs
EGS4 Electron Gamma Shower 4 (Computer Code).
EGUN Electron optics and GUN design program.
EH Office of the Assistant Secretary for Environment, Safety and Health.
EH&S Environmental Health & Safety (Stanford).
EHF European Hadron Facility
EHM Extremely Hazardous Materials.
EHNS Ellis-Hagelin-Nanopoulos-Srednicki
EHS Four-pi detector at CERN.
EHSS Environment, Health, Safety & Security (DOE)
EIA Electrical Institute Associates.
EIA Energy Information Agency.
EIE Electronics and Instrumentation section (Controls Department).
EIL Environmental Impairment Liability.
EIP Energy Isolation Plan
EIR Environmental Impact Report. (CEQA)
EIR External Independent Review. (DOE)
EIS Environmental Impact Statement. (NEPA)
ELEC Electronic combination.
Electromagnet Current See EMC.
Electron Volt See eV.
Electron-Gamma Shower See EGS.
Electronic Bulletin Board System See BBS.
Electronic Mail See E-Mail.
ELENA Extra Low ENergy Antiproton ring. (CERN)
ELETTRA Elettra Sincrotrone Trieste, a national laboratory in Basovizza, Italy.
ELFE Electron Laboratory For Europe
ELISA Electron LInear Superconducting Accelerator.
ELM ELectroMagnetic
ELP Equipment-specific Lockout Procedure.
ELSA ELektronen-Stretcher-Anlage (electron stretcher facility). (Germany)
EM Engineering Model. (FGST)
EM office of Environmental Management. (DOE)
EM ElectroMagnetic.
EM Emission Monitor.
EMACS Editing MACroS. Written by Richard Stallman at the MIT AI lab, EMACS is a program editor in UNIX with an
entire LISP system which features high memory utilization and functions and programs that return values.
EMAG ElectroMagnet.
E-Mail Electronic Mail. A network application that allows users to send mail electronically. E-mail systems can be
included as a basic piece of a network operating system (with relatively limited functionality) or as full applications
(with significantly enhanced functionality) that run on top of the network operating system.
E-Mail Address A name that identifies an electronic post office box on a network where e-mail can be sent. Different
types of networks have different formats for e-mail addresses. On the Internet, all e-mail addresses have the form [name]@[domain name].
EMBL European Molecular Biology Lab.
EMC ElectroMagnet Current. A klystron summary display message indicating that the electromagnet current is out of
tolerance. (Focusing magnet.)
EMC European Muon Collaboration (CERN)
EMC Emergency Management Coordinator.
Emergency (Chemical) A situation created by an accidental release or spill of hazardous chemicals which poses a threat
to the safety of workers, residents, the environment, or property.
Emergency Off (Button) Large red buttons, located in the beam housings, and used to turn off both beam and electrical
hazards (including the VVS's) in an emergency situation.
Emergency Operations Center See EOC.
EMIS ElectroMagnetic Isotope Separators
Emission Pollution discharged into the atmosphere from smokestacks, other vents, and surface areas of commercial
or industrial facilities, from residential chimneys, and from motor vehicle, locomotive, or aircraft exhausts.
Emissions Trading EPA policy that allows a plant complex with several facilities to decrease pollution from some
facilities while increasing it from others, so long as total results are equal to or better than previous limits. Facilities
where this is done are treated as if they exist in a bubble in which total emissions are averaged out. Complexes that
reduce emissions substantially may `bank ‘their `credits' or sell them to other industries.
Emittance A measure of the quality of a beam with regard to the tightness and uniformity of the momentum of its
individual particles. Consider a space where each particle is defined by its position x and its angle x'. Then the
emittance is the area of the ellipse enclosing the particles within one sigma (s), defined as above. The emittance (e)
is also related to the size of the beam bys = square root eB, where B is the Beta function.
Emma Bump Used in the LINAC as a local closed Bump for one beam. Four correctors are used to create an oscillation
in one beam in order to compensate for a wakefield problem while making a closed bump in the other beam. Can be used
anywhere in the machine whenever it is necessary to bump only one beam. (Designed by Paul Emma.)
EMO Electric Motor Operator.
EMOD Beam energy in GeV at magnet center from the model, depends on the z location along the LINAC.
EMP Environmental Management Program. (DOE)
EMPH Electronic Measurements Power Supply
EMQG ElectroMagnetic Quantum Gravity
EMR Extraordinary MagnetoResistive effect.
EMS Emergency Management System.
EMS Environmental Management System.
EMS Environmental Management System.
EMSL Environmental Molecular Sciences Laboratory (DOE)
EMSWG Environmental Management System Working Group.
EMUL Emulsions.
EM-X Electron Microscopy-X (Stanford)
ENC Electron-nucleon collider
Encrypted Data or voice information translated into an unreadable form for secure transmission from one point to one
or more other points.
Endangered Species Animals, birds, fish, plants, or other living organisms threatened with extinction by man-made or
natural changes in their environment. Requirements for declaring a species endangered are contained in the Endangered Species Act.
Endangerment Assessment A study conducted to determine the nature and extent of contamination at a site on the National
Priorities List and the risks posed to public health or the environment. EPA or the state conduct the study when a legal a
ction is to be taken to direct potentially responsible parties to clean up a site or pay for the cleanup. An endangerment
assessment supplements a remedial investigation.
End-of-Service-Life Indicator See ESLI.
ENEA Italian National Agency for New Technologies, Energy, and the Environment.
Energy Spectrometer See Spectrometer.
ENLD ENoLoaD. The calculated no-load energy delivered to a DLWG by a klystron. The S-BAND RF energy is integrated for the
duration of one pulse. Enoload is used for lemming and modeling.
ENLIGHT European Network in Light Ion Therapy. ENVIRO
Enoload See ENLD.
Entanglement Term introduced to physics by Edwin Schroedinger to describe the intimate bond that is thought to develop between
quantum systems that have interacted. (Entanglement theory is the basis of current work in quantum computing.)
Entry Door A PPS controlled door used for access to a radiation area. It includes a key-bank, a phone, and a video camera,
and differs from an Entry Gate (the inner door) which has no key but has microswitches for status indication. With a few
exceptions, Entry Doors have two-way communication with MCC, as well as a telephone.
Environment The sum of all external conditions affecting the life, development, and survival of an organism.
Environment, Safety, and Health See ES&H.
Environmental Assessment A written environmental analysis prepared pursuant to the National Environmental Policy Act to
determine whether a federal action would significantly affect the environment, and thus require preparation of a more detailed
environmental impact statement. ENVIRO
Environmental Audit An independent assessment of the current status of a party's compliance with applicable environmental
requirements.
Environmental Fate The movements and chemical changes experienced by a chemical introduced into the environment.
Environmental Response Team EPA experts located in Edison, NJ and Cincinnati, OH, who can provide around-the-clock technical
assistance to EPA regional offices and states during all types of emergencies involving hazardous waste sites and spills of
hazardous substances.
EO Executive Order.
EOC Emergency Operations Center. It is located in the conference room next to the Main Control Room.
EOESH Employee Orientation to Environment, Safety, and Health
EOI Expressions of Interest.
EOIC Engineering Operator In Charge (MCC).
EOP Emergency Operating Procedures.
EORTC European Organisation for Research and Treatment of Cancer.
EoS Equation of State.
EOS Equation Of State.
EP Environmental Protection.
EP Electro-Polishing. (ILC)
EP Extraction Procedure.
EP Toxicity Extraction Procedure Toxicity. A federally-specified test that is designed to identify wastes likely to leach
hazardous concentrations of particular toxic constituents into the groundwater as a result of improper management. (from RCRA)
EPA U.S. Environmental Protection Agency.
EPA Equivalent Photon Approximation
EPA Identification Number (Or EPA Number) The unique number assigned by EPA to each generator, transporter, or TSDF.
EPAC European Particle Accelerator Conference.
EPAC Experimental Program Advisory Committee. The SLAC EPAC meets twice a year and reviews experimental proposals and
advises the laboratory director.
EPCRA Emergency Planning and Community Right-to-know Act of 1986. Also known as SARA Title 111. (42 U.S.C. Sec. 9601 et seq)
EPCS Experimental Physics Control Systems (Acronym for European Physical Society Interdivisional Group on same).
EPD Engineering and Physics Division (LCLS).
EPEAT Electronic Product Environmental Assessment Tool.
EPFL Ecole Polytechnique Fédérale de Lausanne. (Swiss Federal Institute of Technology in Lausanne)
EPhLAN ElectroPhysical LAboratory, of the USSR Academy of Sciences.
EPIC European Photon Imaging Cameras.
EPIC Electron-Proton/Ion polarized beam Collider
EPICS Experimental Physics and Industrial Control System. A computer software package developed by the Los Alamos and Argonne
research facilities and used at SLAC in PEP II, NLCTA and LCLS.
EPIO Emergency Public Information Officers.
EPIP Emergency Preparedness plan Implementing Procedures.
EPO Emergency Power Off.
EPOG European Particle physics Outreach Group.
EPP Elementary Particle Physics OR Experimental Particle Physics
EPP2010 Elementary Particle Physics in the 21st Century. Committee formed as part of the National Academies commission by DOE
and NSF to construct a plan for US participation in the global particle physics community. See: http://www7.nationalacademies.org/bpa/EPP2010.html.
EPR Einstein-Podolsky-Rosen.
EPR Environmental Protection and Restoration, an ES&H Division Department
EPRB Einstein-Podolsky-Rosen-Bohm
EPRI Electric Power Research Institute (Palo Alto, CA)
E-print An electronic manuscript intended for publication but circulated among peers for comment prior to being submitted
for publication.
EPROM Erasable Programmable Read-Only Memory.
EPS European Physical Society.
EPS Encapsulated PostScript.
EPS-AG European Physical Society - Accelerator Group.
EPU Elliptically Polarizing Undulator. (LCLS)
EQMC Extended Quark Meson Coupling
EQSE Enhanced Quasi-Sparse Eigenvector
EQU EQUipment.
Equilibrium In relation to radiation, the state at which the radioactivity of consecutive elements within a radioactive series
is neither increasing nor decreasing.
ER Office of Energy Research.
ER Employee Relations (SLAC).
ERA-Net European Research Area Network.
ERAP Emergency Readiness Assurance Plan.
ERC European Research Council.
ERG Employee Resource Group.
ERL Energy Recovery/Recovering Linac.
ERM Enterprise Risk Management. (Stanford)
ERMP Enterprise Risk Management Program.
ERO Emergency Response Organization. (SLAC)
ERP Enterprise Resource Planning.
ERT Emergency Response Team.
ERULF Energy Research Undergraduate Laboratory Fellowship. (Formerly SISE)
ERWM Environmental Restoration and Waste Management.
ES&H Environment, Safety, and Health.
ES&HD Environment, Safety, and Health Division. A SLAC Division which absorbed the former ESO and Radiation Physics Departments.
ESA European Space Agency.
ESA End Station A.
ESA Endangered Species Act
ESAB Energy Secretary Advisory Board (DOE).
ESASE Enhanced Self-Amplified Spontaneous Emission.
ESB Executive Safety Board.
ESB End Station B.
ESC Electrical Safety Committee.
ESC Environmental Service Committee.
ESC Extended Soft Core.
ESC End Station C.
ESCO Energy-Saving COmpany.
ESD Energy Sciences Directorate (SLAC)
ESD Event-Summary Data
ESD Electronics and Software engineering Department (SLAC). Created October, 2000 when former Controls and Power Conversion
Departments were combined.
ESE Equilibrium Self-Energy.
ESF Exploratory Studies Facility.
ESF Electronic Structure Factory. (ALS)
ESFRI European Strategy Forum on Research Infrastructures.
ESGARD European Steering Group for Accelerator R&D.
ESH Environment, Safety and Health Division (SLAC)
ESHAC Environmental Safety and Health Advisory Committee.
ESI Electronically Stored Information.
ESLI End-of-Service-Life Indicator. A colorimetric indicator on an air- purifying respirator which indicates when to discard
the purification element.
ESM Electron Spectro-Microscopy.
ESnet The network backbone for all DOE Energy Research Programs (High Energy and Nuclear Physics, Basic Energy Sciences, Scientific
Computing and Health and Environmental Research). It replaced the communication facilities used by the existing High Energy Physics
network (HEPnet) and the Magnetic Fusion Energy network (MFENET) giving these networks increased bandwidth and connectivity
(see also HEPnet and MFENET).
ESO European Southern Observatory. An European organization for astronomical research.
ESO Environment and Safety Officer, also Environment and Safety Office. See also ES&H
ESO Electrical Safety Officer. (SLAC)
ESPP European Strategy for Particle Physics.
ESR Experimental Storage Ring. (Darmstadt)
ESR Electron Spin Resonance.
ESRD Experimental Systems and Research Department
ESRF European Synchrotron Radiation Facility. (Grenoble, France)
ESS Energy Summer School.
ESS European Spallation Source. (Lund, Sweden)
ESS-DIVE Environmental Systems Science Data Infrastructure for a Virtual Ecosystem (DOE)
ESSM Extended Supersymmetric Standard Model.
ESTB End Station Test Beam.
ESTRO European Society for Therapeutic in Radiology and Oncology.
ESUO European Synchrotron User Organization.
ESWP Elevated Surface Work Plan.
ETA Linear Energy Dispersion (for the Greek letter eta).
ETA East Turn Around. The positron transport line after the booster where the line turns back west to the beginning of
the LINAC (for re-injection).
ETA Employee Training Assessment.
ETC Estimate To Complete.
ETC Extended TechniColor
ETH Swiss Federal Institute of Technology (Zurich).
Etherne t A lower-level network protocol, originally developed by Xerox Corporation, used to communicate between
computers in a local network (LAN). Communication takes place by means of modulation of radio frequency signals. On an
Ethernet, interface cards share a common cable by listening before transmission and transmitting only during a break in
traffic, a technique called a 'carrier-sense multiple access w/collision detection (CSMA/CD)'.
Ethernet 10BaseT An Ethernet configuration using unshielded twisted pair wire and a small plastic connector (RJ-45)
to connect workstations, printers, etc. on an Ethernet.
ETOILE Espace de Traitement Oncologique par Ions Legers dans le cadre Europeen, a national center for light-ion
hadron therapy in France.
ETR Estimated Time of Repair.
ETS Engineering and Technical Support.(SLAC)
EuCARD European Co-ordination for Accelerator Research and Development.
EUDET European-Union-funded project assembling 31 European institutes and 20 international associates to prepare infrastructures for the ILC.
EUP Experimental Use Permit. (from FIFRA)
Euro NNAC European Network for Novel ACcelerators.
European Academic Research Network See EARN.
EUROTeV EUROpean design study towards a global TeV linear collider.
EUV Extreme Ultraviolet
EV Earned Value.
eV Electron Volt. A unit of energy equal to the work done by moving an electron across a potential difference of one volt. A measure of
particle energy or relativistic mass (when normalized with c-1).
EVLA Expanded Very Large Array.
EVMS Earned Value Management System. (DOE certification)
EW Eye Wash.
EW ElectroWeak
EWP Electrical Work Plan.
EWP ElectroWeak Penguins
EWPT ElectroWeak Phase Transition.
EWS Employee Web Site. (Taleo)
EWSB Electro-Weak Symmetry Breaking.
ExaFEL Exascale computing for Free Electron Laser
EXAFS Extended X-ray Absorption-edge Fine Structure.
Exception Report A report that generators who transport waste off-site must submit if they do not receive a properly completed copy
of their manifest within 45 days of the date on which the initial transporter accepted the waste.
excitons electron-hole pairs
EXE EXEcutable program image file.
Executable Program Image File See EXE.
EXELFS EXtended Electron Fine Structure
Exempt Solvent Specific organic compounds that are not subject to requirements of regulation because they have been deemed by EPA to
be of negligible photochemical reactivity.
Exempted Aquifer Underground bodies of water defined in the Underground Injection Control program as aquifers that are sources
of drinking water (although they are not being used as such) and that are exempted from regulations barring underground injection activities.
Exergy The useful portion of energy.
EXIST Energetic X-ray Imaging Survey Telescope (proposed).
EXO Enriched Xenon Observatory.
Experiment In high energy physics, a research activity that makes use of an accelerator/detector and is individually numbered and
named by the relevant national laboratory.
Experiment Schedule See Operations Schedule.
Experiment String A series of experiments that are linked together by overlapping research interests and overlapping individual
and institutional members of a collaboration.
Expert System A method and technique for constructing human-machine systems with specialized problem-solving expertise. The pursuit
of this area of artificial intelligence research has emphasized the knowledge that underlies human expertise and has simultaneously
decreased the apparent significance of domain-independent problem-solving theory. An expert system assists or replaces an expert
to solve problems.
Exposure The amount of radiation or pollutant present in an environment which represents a potential health threat to the
living organisms in that environment.
Exterior Gateway Protocol See EGP.
Extraction Positron 1 See EP01.
Extraction Positron 2 See EP02.
Extraction Procedure Toxicity See EP Toxicity.
Extremely Hazardous Substances Any of 406 chemicals identified by EPA on the basis of toxicity, and listed under SARA Title III.
The list is subject to revision.
EXTRL EXTRaction Line.
EYH Expanding Your Horizons. (NGO)
EYM Einstein-Yang-Mills
EYMD Einstein-Yang-Mills dilation
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F Focusing
F Wastes A federal waste category comprised of wastes from nonspecific sources.
F&A Finance and Audit committee (BoO)
F&O Facilities and Operations. (SLAC)
FA Fire Alarm.
FAA Federal Aviation Administration.
FAC Federal Administrative Charge.
FAC Facilities Office. Merged with Plant Engineering in 2000 and re- named Site Engineering and Maintenance (SEM).
FACET Facility for Advanced Accelerator Experimental Tests. (SLAC)
FACP Fire Alarm Control Panel.
Facsimile see Fax.
FACTS Foreign Access Central Tracking System. (DOE)
FADC Flash Analog-to-Digital Converter.
FAIR Facility for Antiproton and Ion Research.(Germany)
FALC Funding Agencies for Large Colliders.
FALM Fire ALarM.
FAN Facilities Action Notice. -->
FAQ Frequently Asked Question. Pronounced as separate letters or as faK, a FAQ is a document that answers questions
about some technical topic. Frequently, FAQ's are available electronically, and are formatted as help files or hypertext documents.
FAR Federal Acquisition Regulation
Faraday Cup See FARC.
FARC FARaday Cup. A device designed to stop an accelerated beam and measure the integrated charge. Some are also used to
park beams at low rep rates for short periods. FARCs are usually connected to ground through a current measuring device so
that the integrated current in the beam may be measured.
FaST Faculty and Student Teams.
FAST Five-hundred meter Aperture Spherical Telescope. (China)
FaST Faculty and Student Teacher program (DOE)
Fast Fault Finder Electronic safety interlock system that diagnoses klystron or Marx modulator malfunctions.
Fast Time Plot See FTP.
FAT Factory Acceptance Test
Fault Lock Out See FLK.
Fault Tolerance The ability of hardware to tolerate the breakdown of any major components, such as CPUs, hard drives and
power supplies. Fault tolerance is typically provided by supplying two or more of the same component, with the additional
hardware serving on a standby basis. True fault tolerance provides standby hardware that instantaneously takes over for
malfunctioning hardware elements in a completely transparent manner with, ideally, absolutely no loss of data and no
processing downtime.
Fax (verb) To send a document via a facsimile machine, which is a device that can send or receive pictures and text
over a telephone line. (noun) A document sent or received via a fax machine.
FB FeedBack.
FB29 A microprocessor dedicated to the steering feedback through the collimators at the end of the LINAC.
FB31 A microprocessor dedicated to the Fast Energy Feedback at the end of the LINAC.
FB69 A Microprocessor controlling IP devices.
FBR Field Budget Request.
FCAL Forward liquid argon CALorimeter of the ATLAS detector. (CERN)
FCC Federal Communications Commission. Federal commission that sets policy and regulates the U.S. communications
industry under the authority of the Communications Act of 1934.
FCEB Federal Civilian Executive Branch
FCEV Fuel Cell Electric Vehicle.
FCM Field Construction Manager.
FCNC Flavor Changing Neutral Currents
FCSM Finance and Supply Chain Management.
FD Fluorescence Detector (Auger Observatory).
FD Fire Damper.
FDA Free Differential Algebra
FDDI Fiber Distributed Data Interface. A set of ANSI protocols for sending digital data over fiber-optic cable.
FDDI networks are token-passing networks, and support data rates of up to 100Mbps (100 million bits) per second. FDDI
networks are typically used as backbones for wide-area networks.
FDIRC Focused Detection of Internally Reflected Cherenkov light.
FDTHRU FeeD THRoUgh.
FDW Financial Data Warehouse.
Federal Communications Commission. See FCC.
Federal Telecommunications System See FTS.
FEE Front-End Enclosure (LCLS). Also known as XTES (X-ray Transport and Experimental Systems)
FEFF An automated program for ab initio multiple scattering calculation s of XAFS an XANES spectra for cluster of
atoms. (University of Washington).
FEH Far Experimental Hall. (LCLS)
FEIS Final Environmental Impact Statement.
FEL Free-Electron Laser
FEMA Federal Emergency Management Agency.
FEMP Federal Energy Management Program.
Femtobarn 10-39 square centimeters (10-15 of a barn).
Femtosecond One quadrillionth of a second.
FEO Federal Energy Office.
FEP Facility Emergency Plan.
FERMI FERMI gamma-ray space telescope.
FERMI Free Electron Radiation and Matching Instrumentation
FERMI Federal Electronic Records Modernization Initiative (NARA)
Fermi solution A method for generating approximate solutions quickly. Named after Enrico Fermi, who had considerable
ability in this area. The method requires that one know a close approximation tithe range into which the computational
results should fall.
FERMILAB See FNAL
FES Fusion Energy Sciences.
FEWG Fugitive Emissions Working Group.
FF Final Focus.
FF Finding Foil.
FFA Federal Facility Agreement.
FFAG Fixed-Field Alternating Gradient accelerators.
FFBK Fast FeedBacK.
FFD Fitness For Duty.
FFRDC Federally Funded Research and Developement Centers.
FFT Fast Fourier Transform
FFTB Final Focus Test Beam. (SLAC)
FFZ Fairlie-Fletcher-Zachos
FGS Fine Guidance Sensor. (JWST)
FGST Fermi Gamma-ray Space Telescope. (Formerly called GLAST)
FIA Factory Insurance Association.
FIAT PHasing, Isolation, Attenuation, and Trigger. (The F is phonetic.) Double-width racks that stand at every
klystron/modulator station and hold electronic chassis that relate to the klystron/modulator functionality and protection.
FIB Focused Ion Beam.
Fiber Distributed Data Interface See FDDI.
Fiber Optics A data transmission medium made of tiny threads of glass or plastic that transmit huge amounts of data
at the speed of light. The light is normally generated by a light emitting diode(LED) or a laser.
Fiberglass See FRP.
FICA Federal Insurance Contributions Act.
FID Free Interface Diffusion.
Fieldbus A local area network technology used for the control of sensors and actuators in industrial applications
such as data acquisition and control. Normally a Fieldbus network uses transmission media such as twisted-pairs cables.
The Fieldbus communication protocol is designed to exchange short command messages among devices such as actuators,
sensors, controllers, general-purpose computers and other industrial devices connected on a network. Several proprietary
Fieldbus protocols exist, including Foundation Fieldbus, CANbus , BITBUS, WorldFIP, and Profibus.
FIFO First In First Out. A computer jargon term referring to the order data is transferred, as in a queue.
FIFRA Federal Insecticide, Fungicide and Rodenticide Act. (7 U.S.C. Sec. 136 et seq)
File Transfer Protocol See FTP.
FIMS Facilities Information Management System
Final Focus Test Beam See FFTB.
Final Triplet The last three quadrupole magnets in the beam line optics of the Final Focus just before the IP.
Finger A standard protocol specified in RFC 742 which lists who is currently logged in on another host.
FIPS Federal Information Processing Standards. Developed by National Institute of Standards and Technology (NIST) in accordance with the
Federal Information Security Management Act (FISMA) for federal computer systems
FIR Finite Impulse Response
FIRAS Far-Infrared Absolute Spectrophotometer
Fire P Fire Point. The lowest temperature at which a mixture of air and vapor continues to burn in an open container
when ignited. It is usually above the flash point.
Fire Point See Fire P.
FIRST Faint Images of the Radio Sky at Twenty centimeters.
Fiscal Year See FY.
FISMA Federal Information Security Management Act of 2002.
FIT Fit to previously existing data.
FITS Flexible Image Transport System. Originally an astronomical image file format, now also used for tabular data.
Fixation A process whereby waste is made unchangeable and/or stationary.
FJPPL France-Japan Particle Physics Laboratory.
FJ-PPL France-Japan Particle Physics international associated Laboratory.
FLAMINGOS FLoridA Multi-object Imaging Near-infrared Grism Observational Spectrometer.
Flammability Range For a given substance, that range of percentages from the LEL to the UEL, any of which will
ignite if provided an ignition source.
FLASH Free-electron LASer in Hamburg. (DESY)
Flash P Flash Point. The lowest temperature at which a liquid will give off enough flammable vapors at or near its surface
such that in an intimate mixture with air and a spark or flame, it ignites.
Flash Point See Flash P.
FLCO FLoor CleanOut.
FLIC Fat Link Irrelevant Clover.
Flip Coil A device for measuring the strength of a magnetic field. It consists of a coil which rotates through the B
field of the magnet, inducing a current in the coil which is proportional tithe field and the rotational velocity of the
coil. The field strength thus measured may be correlated to a specific beam energy.
Flipper A phase shifter used to delay an RF phase by 180 degrees as for the FIDO norm beam subharmonic buncher phase.
FLK Fault Lock Out. A klystron summary display message indicating a modulator fault lockout.
Flow Switch An interlocked device protecting beam line elements, such as magnets, from a cooling system failure
FLRW Friedmann-Lemaitre-Robertson-Walker
FLS First Level Supervisor
FLTSW FLoaT SWitch.
FLUENCE FLuid-ENhanced Crystal Engineering.
Fluidized-Bed Incineration A process whereby wastes are injected into agitated beds of inert granular material and
burned. This method is suitable for sludges and liquid waste: solid wastes may need grinding.
FLUKA A multiparticle transport computer code, developed at INFN and CER N.
FMA Fisher Matrix Analysis.
FMD Facilities Management Designee.
FMEA Failure Modes and Effects Analysis
FMECA Failure Mode, Effects, Criticality Analysis.
FMO Fire Marshal's Office.
FMPS Fermilab MultiParticle Spectrometer.
FNAL Fermi National Accelerator Laboratory (Batavia, IL). Also known as FERMILAB.
FOA Funding Opportunity Announcement (DOE)
FOC Facilities Operations Center. Also used for Facilities Operations Control group.
FOCUS center for the advancement of Frontiers in Optical Coherent Ultrafast Science. (NSF)
Focus Drift Defocus Drift See FODO.
FODO FOcus drift DefOcus drift. A beam transport line optional lattice composed of a focusing quadrupole
and a defocusing quadrupole separated by equal drift sections.
FOFB Fast Orbit Feed Back system.
Foils Refers to the energy spectrum monitors used in the ETA and the WTA. Composed of six bpms strips (there
are actually no foils). Also refers to strips on the BSY TUD for measuring energy spectrum.
Folio The online information resource of the Stanford University libraries. It includes the online catalog,
INSPEC, MEDLINE, and other databases.
FONSI Finding of No Significant Impact (as the result of an environmental impact report)
Footprint The shape and area of floor space required for a piece of equipment.
FOPT Fixed Order Perturbation Theory
Form R Toxic Release Inventory.
FORTRAN FORmula TRANslator. The oldest high-level programming language, designed by John Backus for IBM
in the late 1950's.
Forward Phasing 1. To adjust the RF phase of a particle beam to add energy to the particle bunch. 2. To compensate
for wakefields by keeping E Tail greater than E Head.
Four By Six The section of the PRL near Sector 19. It includes four bends of six degrees each.
FOV Field-Of-View.
Fox Phase Shifter The RF phase shifter directly above each LINAC klystron. Designed by A. Gardner Fox, after
whom the device is named.
FP7 Seventh Framework Programme (European Union).
FPCD Final Procurement and Construction Design.
FPD Federal Project Director.
FPGA Field Programmable Gate Array.
FPM see JCC FPM
FPP Fall Protection Plan.
FPP Fast Pulse Pickup.
FQDN Fully Qualified Domain Name. The FQDN is the full site name of a system, rather than just its hostname. For example,
the system, lisa, at Widener University has a FQDN of:lisa.cs.widener.edu.
FQH Fractional Quantum Hall effect
FQHE Fractional Quantum Hall Effect.
FQXi Foundational Questions in Physics and Cosmology.
FR Federal Register.
FRA Federal Railroad Administration.
FRCP Federal Rules of Civil Procedure.
FRED FOX Ruby Event Display. Graphics client used for event display (GLAST).
FRIB Facility for Rare Isotope Beams. (Michigan State)
FRMG FoRMinG.
FRP Fiber-Reinforced Plastic (fiberglass).
FRS Functional Requirements Specification.
FRW Friedmann-Robertson-Walker
FS Femto-Second.
FS See Flow Switch.
FSAD Failure Safety Analysis Document.
FSAD Final Safety Analysis Document
FSAR Final Safety Analysis Report.
FSCM Finance and Supply Chain Management. (SLAC)
FSHC Faculty Staff Health Center (Stanford).
FSI Final State Interaction.
FSIM Financial Services Integration Meeting
FSR Final State Radiation.
FSRQ Flat-Spectrum Radio Quasar.
FSUST Former Solvent Underground Storage Tank.
FSUSY Fractional SUperSYmmetry
FT Final Telescope.
FTAM File Transfer Access Method, ISO standard ISO 8571.
FTDT Finite-Difference Time-Domain.
FTE Full Time Equivalent.
FTFT Finite Temperature Field Theory.
FTIR Fourier Transform InfraRed
FTM Facilities Transition Manager
FTMS Foreign Travel Management System.
FTMS Federal Test Method Standard.
FTOOLS NASA-sponsored software used to examine and manipulate the contents of FITS (image and tabular data) files.
FTP Field Task Proposal.
FTP File Transfer Protocol. The Internet standard protocol for transferring text and binary files from one computer to another.
FTP Fast Time Plot. A klystron diagnostic software package that uses a variable sample gate to generate plots of klystron
parameters vs. time. COMPUTING
FTPC Forward Time Projection Chamber
FTR Federal domestic TRavel per diem.
FTS Federal Telecommunications System. A US Government network of leased long-distance lines, managed and operated by the
General Services Administration to provide long-distance service at a lower cost than commercial service. (defunct)
Fudge Factor Used by LEM to scale EACT to the desired energy. Makes EACT equal to EMOD at the end of the LINAC. The
fudge factor distributes energy errors of unknown source evenly through the LINAC.
Fudge Factor Any factor added to or multiplied by a theoretically derived equation to make it more closely match the
real world. Fudge factors compensate for second and third order effects that are often too cumbersome to include in the
theory, or for indeterminate misalignments in the hardware.
Full Duplex Data transmission in both directions at the same time. See also Half Duplex.
Fully Qualified Domain Name See FQDN.
Fumes Smoke-like particles of metals suspended in air.
FUSE Far Ultraviolet Spectroscopic Explorer.
FUSRAP Formerly Utilized Sites Remedial Action Program (DOE).
FV Fast acting vacuum Valve. Remotely operated accelerator valve.
FWHM Full Width at Half Maximum. (Beam focus measure)
FWP Field Work Proposal.
FWPCA Federal Water Pollution Control Act (amended by CWA).
FWS Fast Wire Scanner. Also Fast WSCNR.
FXI Femtosecond X-ray Imaging.
FY Fiscal Year. SLAC operates on the Federal Fiscal Year which starts 1 October and ends 30 September. Fiscal years are
named for the year in which they end. ex. FY99 = 1 Oct 1998 thru 30Sep 1999.
FZJ ForschungsZentrum Informatik. (German research center)
FZK ForschungZentrum Karlsruhe. (a German science and engineering research institution)
FZR ForschungZentrum Rossendorf, a research institute in Germany.
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G Giga, meaning 10to the 9th power, or billions of . . .(e.g.: gigabits).
G&A General and Administrative.
G4 GEANT4.
GA GAuge / GAge.
GAA General Access Areas
GAAC German American Academic Council
GAAP Generally Accepted Accounting Practices.
GaAs Gallium Arsenide. A compound used in light emitting diodes and very fast semiconductors. It is used in SLC fast clock
chips for fiducializing and synchronizing the LINAC with PEP, and is also the basis for cathodes in the polarized guns.
GAC Granular Activated Carbon.
GADZOOKS Gadolinium Antineutrino Detector Zealously Outperforming Old Kamiokande Super.
GAINS Girls Advancing In STEM
Galaxy Zoo A crowd-sourcing project to allow interested members of the public to classify by type the galaxies imaged by
the Hubble Space Telescope.
GALEX GALaxy Evolution eXplorer/
Gallery The two-mile-long building where the LINAC klystrons and LINAC magnet power supplies are housed. The actual LINAC beam
pipe is approximately 25 feet underground below the gallery.
Gallium Arsenide See GaAs.
GALPROP Numerical model of particle propagation in the Galaxy incorporating as much realistic input as possible.
GAM2 IHEP hodoscope Cherenkov gamma calorimeter GAMS-2000.
GAM4 CERN hodoscope Cherenkov gamma calorimeter GAMS-4000.
Gamma One of the Twiss parameters, which relates alpha and beta: beta gamma = 1 + alpha(exp 2). It is also the relativistic
factor used in acceleration calculations.
Gamma Ray A high energy photon. PHYSICS
Gamma, Electron, and Muon Experiment See GEM.
GAN GAlactic Neighborhood.
GAN Global Accelerator Network (proposed).
GANIL Gran Accélérateur National d'Ions Lourds.
GAO Government Accountablility Office - US (formerly General Accounting Office).
Gap Monitor see GAPM.
Gap Voltage The electrical field between the 2 irises of an RF cavity.
GAPM GAP Monitor. A break in the conductive beam pipe which is bridged by a ring of ceramic in parallel with a
resistance that provides the proper impedance. The beam induces a voltage drop across the resistance, which may be
measured and displayed on an oscilloscope. Also called wall current monitor, since it measures the voltage induced
by interrupting the current traveling through the beampipe due to the passing of the beam.
GARD General Accelerator Research and Development.
GASU Global trigger, Acd interface, and Signal distribution Unit.
GATE Geant4 Application for Tomographic Emission.
Gated Analog to Digital Converter See GADC.
Gateway A special-purpose dedicated computer that attaches to two or more networks and routes packets from one
network to the other. In particular, an Internet gateway routes IP diagrams among the networks it connects.
Gateways route packets to other gateways until they can be delivered to the final destination directly across one physical network.
Gateway to Gateway Protocol See GGP.
Gauss A unit of magnetic flux density, symbol G. Named after the mathematician Karl Friedrich Gauss (1777-1855)
Gaussian A statistical distribution of particles or objects which is `bell shaped' and can be approximated
by the Gauss distribution law. Named after the mathematician Karl Friedrich Gauss(1777-1855).
GB See Gigabyte.
GBFEL Ground-Based Free Electron Laser.
GBM GLAST Burst Monitor experiment. HEP
GBT Green Bank Telescope (NRAO-West Virginia).
GC/MS Gas Chromatography/Mass Spectroscopy.
GCEP Global Climate and Energy Project. A long-term collaborative effort to conduct fundamental research on a global
energy system that would significantly reduce greenhouse emissions.(Stanford)
GCM Generator Coordinate Method
GCP General Cascade Program
GCR Galactic Cosmic Rays
GCT Galaxies across Cosmic Time.
GD&T Geometric Dimensioning & Tolerancing.
GD&T Geometric Dimensioning and Tolerancing.
GDE Global Design Effort.(ILC)
GDH Gerasimov-Drell-Hearn
GDP General Development Plan.
GDR Giant Dipole Resonance
GDS Global Directory Service. For global namespace, which starts from a global root and divides into a hierarchical
tree at country, organization, locality, cell, and other points. XDS from X/Open is the general purpose API for standard applications.
GEANT A pan-European research and education network and the corresponding four-year project set up by a Consortium of
27 National Research and Education Networks (NRENs) across Europe.
GEANT2 Successor to GEANT, see GEANT.
GEANT3 A computer program for detector description and simulation.
GEANT4 GEometry ANd Tracking. Toolkit for the simulation of the passage of particles through matter (CERN)
GEM Graduate Engineering for Minorities.
GEM Gas-Electron Multiplier.
GEMS Graduate degrEes for Minorities in Engineering and Sciences. (National consortium)
GEMS Galaxy Evolution from Morphology and Spectral energy distributions .
General Purpose Interface Bus See GPIB.
Generator The person or facility who, by nature or ownership, management, or control, is responsible for causing or
allowing to be caused, the creation of hazardous waste.
GENI GENeral Interface.
GERDA GERmanium Detector Array. (Italy)
GERT General Employee Radiological Training.
GES Geological and Environmental Sciences.(Stanford)
GeV Giga(billion) electron Volt. An electron volt is the unit of energy equal to the work done by moving an electron
across a potential difference of one volt.
GFCI Ground Fault Circuit Interrupter.
GFE Government-Funded Equipment.
GFP Government-Furnished Property.
GG1 Global Group 1 (Parameters). (ILC)
GG2 Global Group 2 (Instrumentation and Controls). (ILC)
GG3 Global Group 3 (Operations and Availability). (ILC)
GG4 Global Group 4 (Conventional Facilities and Siting). (ILC)
GG5 Global Group 5 (Cost and Engineering) (ILC)
GG6 Global Group 6 (Options). (ILC)
GGF Global Grid Forum. A community-initiated forum of individual researchers and practitioners working on distributed
computing, or grid technologies. Particle Physics Data Grid (PPDG) is a part of this forum.
GGP Gateway to Gateway Protocol. The protocol core gateways use to exchange routing information. GGP implements a
distributed shortest path routing computation. Under normal circumstances, all GGP participants will reach a steady
state in which the routing information at all gateways agrees.
GHG GreenHouse Gas.
GHP Geroch-Held-Penrose
GHS Garfinkle-Horowitz-Strominger
GHZ Greenberger-Horne-Zerlinger
GHZ GigaHertZ. (Written GHZ on drawings, or GHz in text.)
GIC Gauge Invariant and Covariant
gif Graphics Interchange Format. Pronounced jiff or giff (hard g). A bit-mapped graphics file format used by the
World Wide Web, CompuServe and many BBSs. GIF supports color and various resolutions. It also includes data compression,
making it especially effective for scanned photos.
GIFT Goldstones Instead of Fine Tuning
Giga see G
Gigabyte 2 to the 30th power (1,073,741,824) bytes. One gigabyte is equal to 1,024 megabytes. Abbreviated G or GB.
GIM Glashow-Iliopoulos-Maiani
Girder A support structure for the Accelerator. In the LINAC most girders are 40 feet long. Note that the SLC
component numbering system is referenced to girder numbers.
GIS Geographic Information System
GISMo Grid Integration Systems and Mobility
GISO General Industry Safety Order. (Cal/OSHA)
GITC General Information Technology Controls
GIXS Grazing Incidence X-ray Scattering.
GKZ Gelfand-Kapranov-Zelevinski
GL General Ledger.
GLAD Gev Laser Accelerator Developments (Japan).
GLAM Geballe Laboratory for Advanced Materials (Stanford).
GLARE Gemini Lyman-Alpha at Reionization Era.
GLAST Gamma-ray Large Area Space Telescope. A large aperture, space-based, gamma-ray detector. Also, an international
collaboration involving SLAC, Stanford, NASA, and groups in Japan Italy, France and Sweden. Renamed Fermi Gamma-ray
Space Telescope (FGST) in August 2008.
GLC Global Linear Collider group. (KEK)
GLC Global Linear Collider.
GLD Concept detector for the ILC (Global Large Detector).
GLEAM GLAST Event Analysis Machine.
GLIF Global Lambda Integrated Facility.
GLIMPSE Galactic Legacy Infrared Mid-Plane Survey Extraorinaire.
Glow discharge A luminous electrical discharge without sparks through a gas.
Gluino In models of supersymmetry, the partner of the gluon.
GMO Gell-Mann-Okubo
GMOR Gell-Mann-Oakes-Renner
GMP Ground water Monitoring Plan.
GMR Giant MagnetoResistance.
GMRES Generalized Minimum RESidual.
GMSB Gauge Mediated Supersymmetry Breaking
GNAT Global Network of Astronomical Telescopes.
Go Around Frequency In a storage ring, the number of circumnavigations of the ring made by any given bunch in one
second (expressed in Hertz).
Gold Phase The phase of a klystron with maximum efficiency (if the bunch is riding near the crest of the RF wave). The
gold phase is the phase for the maximum energy transfer.
GOSIP Government Open Systems Interconnection Profile. A government specification (a collection of protocols referred to as
a profile) designed to ensure that communications and networking software used by the government is indeed OSI-compliant
when OSI compliance is required.
GOSSIP Gas On Slimmed SIlicon Pixel.
Government Open Systems Interconnection Profile See GOSIP.
GP Guiding Principle (ES&H)
GPCRs G Protein-Coupled Receptors.
GPD Generalized Parton Distributions.
GPDF Generalized Parton Distribution Function.
GPFS General Parallel File System (Computing)
GPIB General Purpose Interface Bus. A communication protocol for small computers like PCs or MACs to interface with
peripherals, instruments, or other devices. If you want your PC to start your coffee before you wake up in the morning, you will need a GPIB.
GPMP Ground water Protection Management Program.
GPMPP Ground water Protection Measurement Program Plan.
GPO Group Policy Objects (computing). Policies that are defined for each computer or user.
GPP General Plant Project.
GPR Gaussian Process Regression.
GPS Global Positioning of Spin
GPU Graphics Processing Unit.
GR Gamma Ray.
GR General Relativity
GRACE An automatic scattering amplitude generator that enables theoretic al calculations to match the required high-precision
data analyses required by high-energy physics experiments.
Gray The International System (SI) unit of absorbed dose. One gray is equal to an absorbed dose of 1 Joule per kilogram (100 RADS).
Gray Water The term given to domestic wastewater composed of wash water from sinks, kitchen sinks, bathroom sinks
and tubs, and laundry tubs.
GRB Gamma-Ray Burst.
GREEN-RF Generator for REcovering ENergy from RadioFrequency. (A type of klystron)
Grid see GGF.
GRIDCC Grid-enabled Remote Instrumentation with Distributed Control and Computation.
GridKA Grid computing centre KArlsruhe. (Germany)
Gridpix Detector building block combining the timepix chip with InGrid.
GriPhyN Grid Physics Network (pronounced griffin). A system for handling vast amounts of physics data. Participants include the
Sloan Digital Sky Survey, the Laser Interferometer Gravitational-Wave Observatory, and two HEP experiments at CERN's LHC.
GRIT Gamma-Ray Inspection Technology
GROG General Relativistic Overturn of Gravity.
Gross Alpha Particle Activity Total activity due to emission of alpha particles. Used as the screening measurement for radioactivity
generally due to naturally-occurring radionuclides. Activity is commonly measured in picocuries.
Gross Beta Particle Activity Total activity due to emission of beta particles. Used as the screening measurement for radioactivity
from manufactured radionuclides since the decay products of fission are beta particles and gamma ray emitters. Activity is commonly
measured in picocuries.
Ground Water Water below the land surface in a zone of saturation.
Growler A small damping ring dipole magnet used to generate an oscillation for tune measurement purposes. When energized, it will
excite the beam to oscillate at its natural resonant frequencies.
GRR Gravitational Radiation Reactions
GRS Gregory-Rubakov-Sibiryakov
GRT General Relativity Theory.
GS Green-Schwarz
GSA General Services Administration. (US)
GSB General Services Building. (SLAC)
GSF Gross Square Feet.
GSFC Goddard Space Flight Center.
GSH Graduate Student Handbook. (SLAC)
GSI Gesellschaft für Schwerionenforschung. (Germany)
GSI Grid Security Infrastructure.
GSP Greene Scholars Program
GSS Government Scientific Source.
GSSC GLAST Science Support Center.
GTF Gun Test Facility. A research project at SSRL aimed at developing the high-brightness electron source that will be needed for
future linac-based X-ray free-electron lasers (FELs) such as SLAC's proposed Linac Coherent Light Source (LCLS). GTF is a photocathode
gun that uses polarized laser light to generate polarized electrons by means of the photoelectric effect on a gallium arsenide cathode.
GTI Good Time Intervals.
GTL Gun-To-Linac. (LCLS)
GUC German University in Cairo.
GUI Graphical User Interface. Sometimes called windowing systems, GUIs are software interfaces which allow mouse and icon
actions in place of typed commands.
GUST Grand Unified Superstring Theories
GUT Grand Unified Theories
GVDM Generalized Vector Dominance Model
GVMD Generalized Vector Meson Dominance Model.
GW Ginsparg-Wilson
GWL Ginsparg-Wilson-Luscher
GWT Google Web Toolkit.
GZK Greisen-Zatsepin-Kuzmin.
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H Horizontal.
H II region A cloud of glowing gas and plasma in which star formation is taking place. Named for the large amount of
ionized atomic hydrogen it contains.
H&C Hoist and Crane.
H&R Hoisting and Rigging.
HA Hazard Assessment.
Hacking The activity of computer enthusiasts who are challenged by the practice of breaking security measures designed to prevent unauthorized
access to one or more computer systems. (Hacking which involves criminal activity is called cracking.)
HAD Hazardous Atmosphere Detector.
Hadron Generic name for members of the largest family of elementary particles. Hadrons interact strongly with one another, usually produce
additional hadrons in collisions at high energy, and are roughly spherical.
HAGGLeS HST Archive Galaxy-scale Gravitational Lens Survey.
Half Duplex Data transmission in either direction, but only one direction at a time.
Half-Life The time required for the elimination of one half a total dose of radiation from the body.
Half-Life The time required for a pollutant to lose half its effect on the environment. For example, the half-life of DDT in the
environment is 15 years, of radium, 1,580 years.
Half-Life The time required for half of the atoms of a radioactive element to undergo decay.
Halogen Any of a group of five chemically-related nonmetallic elements that includes bromine, fluorine, chlorine, iodine, and astatine.
Halogenated Hydrocarbons A group of organic compounds which include one or more atoms of a halogen, e.g., chlorine or bromine, in
their molecular structures.
Halon Bromine-containing compounds with long atmospheric lifetimes whose breakdown in the stratosphere cause depletion of ozone. Halons
are used in fire-fighting.
Handshaking The procedures and standards (protocol) used by two computers or a computer and a peripheral device to establish communication.
HAP Hazardous Air Pollutant.
HAPD Hybrid Avalanche Photo Detector.
HAPPEX Hall A Proton Parity EXperiment, at the US DOE's Jefferson Lab.
HAPS Hazardous Air PollutantS.
HAPS High-Availability Power Supplies.
HAR Hydrogeological Assessment Report. (TPCA)
Hardware Address The low level address used by a physical network. Each type of network hardware has its own addressing scheme.
For example, Ethernet uses 48-bit hardware addresses assigned by the vendor, while proNET-10 uses small integer hardware addresses
assigned when a connection to the network is installed.
Hardware Status See HSTA.
HASC House Armed Services Committee. (US)
HASYLAB The synchrotron radiation laboratory at DESY (Germany)
HAWG Hazard Analysis Working Group.
Hazard A threat to workers, public, environment, or property.
Hazard Evaluation System and Information Service See HESIS.
Hazardous Air Pollutants Air pollutants which are not covered by ambient air quality standards but which, as defined in the
Clean Air Act, may reasonably be expected to cause or contribute to irreversible illness or death. Such pollutants include asbestos,
beryllium, mercury, benzene, coke oven emissions, radionuclides, and vinyl chloride.
Hazardous and Solid Waste Amendments See HSWA.
Hazardous Ranking System The principal screening tool used by EPA to evaluate risks to public health and the environment
associated with abandoned or uncontrolled hazardous waste sites. The HRS calculates as core based on the potential of hazardous
substances spreading from the site through the air, surface water, or ground water and on other factors such as nearby population.
This score is the primary factor in deciding if the site should be on the National Priorities List, and, if so, what ranking it
should have compared to other sites on the list.
Hazardous Substance Any substance named by EPA to be reported if a designated quantity of the substance is spilled in the waters
of the United States or if otherwise emitted into the environment.
Hazardous Substance Any material that poses a threat to human health and/or the environment. Typical hazardous substances are
toxic, corrosive, ignitable, explosive, or chemically reactive.
Hazardous Substance Account See HSA.
Hazardous Waste By-product of society that can pose a substantial or potential hazard to human health or the environment when
improperly managed. Possesses at least one of four characteristics(ignitability, corrosivity, reactivity, or toxicity), or
appears on special EPA lists.
Hazardous Waste Control Account State fund derived from fees paid by operators of onsite and offsite disposal facilities and
used to support the hazardous waste management program of the Department of HealthServices.
Hazards Analysis The procedures involved in (a) identifying potential sources of release of hazardous materials from
fixed facilities or transportation accidents, (b) determining the vulnerability of a geographical area to a release of
hazardous materials, and (c) comparing hazards to determine which present greater or lesser risks to a community.
Hazards Identification Providing information on which facilities have extremely hazardous substances, what those chemicals are,
and how much there is at each facility. The process also provides information on how the chemicals are stored and whether they
are used at high temperatures.
HAZCOM HAZard COMmunication. An Occupational Safety and Health Administration (OSHA) standard that requires all employers to
instruct their workers on the hazards associated with the chemicals they use.
HAZOP HAZard and OPerability study.
HAZWOPER HAZardous Waste OPerations and Emergency Response standard. (OSHA)
HB-0 The bend in the DRIP where the beams returning from the rings get injected back into the LINAC.
HBCPT Heavy Baryon Chiral Perturbation Theory
HBCU Historically Black Colleges and Universities (US).
HBL High-energy cut-off BL Lac object.
HBT Hanbury-Brown-Twiss
HBV Hepatitis B Virus.
HCAL Hadron barrel CALorimeter.
HCM Human Capital Management.
HCP Hazard Communication Program. (SLAC)
HCPBM Heavily Charged Particles in Biology and Medicine.
HCS Hazardous Communications Standard. (OSHA)
HCV Hepatitis C Virus.
HD Higher Derivative.
HDF Hubble deep field.
HDF5 Hierarchical Data Format 5.
HDI How Do I. SLAC Financial and Human Resources gateway.
HDM Higgs Doublet Model.
HDMS Heidelberg Dark Matter Search (Gran Sasso)
HDPE High Density PolyEthylene.
HDSC Hardware DeSCripter.
HDSCP HoDoSCoPe.
HDSPC High Density Spiral Projection Chamber.
HDX Hybrid Damped structure.
HEAD High-Energy Astrophysics Division (American Astronomical Society).
Header The portion of a packet, preceding the actual data, containing source and destination addresses and error-checking fields.
HEASARC High Energy AStrophysics Science ARChive (Goddard).
Heat Exchanger A locked radiation area where radioactive cooling water coming back from the slits, collimators and beam dumps is cooled and
demineralized. (The heat exchange is with the cooling tower water.) The radiation levels in the heat exchangers are monitored by OHP.
Heavy Metals Certain metallic elements having a high density and which are generally toxic, e.g., lead, silver, mercury, and arsenic.
HEB High-Energy Beam.
HEC High-End Computing
HED High-Energy Density science (LCLS).
HEDP High Energy Density Plasma.
HEDS High-Energy Density Science. (LCLS)
HEDSD High Energy Density Science Division
HEE High-Energy Extraction.
HEFT High Energy Focusing Telescope.
HEGRA High Energy Gamma Ray Astronomy telescope. Five-telescope array built in La Palma by a German-Spanish-Armenian collaboration.
HELEN High Energy physics Latin-American-European Network.
HELEN High-Energy Laser Embodying Neodymium. British laser brought to LC LS in 2011.
HELIOS CERN Super Proton Synchroton detector
Helmholtz Coil A coil in which the first and last winding are separated by 2r where r is the radius of the winding. Used to produce a uniform
solenoid field. Designed by Hermann Helmholtz.
Helmholz Alliance Network of German laboratories and universities involved in the LHC and the ILC.
HENIT High-Energy North Injection Transport.
HENP High Energy and Nuclear Physics.
HEP High Energy Physics.
HeP E-tool Hazard Evaluation and Planning Electronic tool. (SLAC ES&H) This tool is an activity-based questionnaire intended for use by non-ESH
staff, in particular supervisors, activity planners and UTR s. The tool identifies SLAC required permits and plans based on responses to the questions.
May be accessed from the WPC website.
HEPA High Efficiency Particulate Air.
HEPAP High Energy Physics Advisory Panel.
HEPC High Energy Photon Conference.
HEPDATA Physics databases maintained at Durham/Raleigh.
HEPL W. W. Hansen Experimental Physics Laboratory, Stanford University. (Formerly, High Energy Physics Laboratory.)
Hepnet High Energy Physics Network. An international network linking computers of High Energy Physics laboratories.
HEPP High Energy and Particle Physics, a division of the EPS.
HEPT HElium Proportional Tubes.
Hertz See Hz. COMPUTING
HERWIG Hadron Emission Reactions With Interfering Gluons. A Monte Carlo program.
HESIS Hazard Evaluation System and Information Service. Sponsored by SDOHS and Cal OSHA. Provides information on chemicals to employers
and employees.
HESS High Energy Stereoscopic System. A next generation system of imaging atmospheric Cherenkov telescopes aimed at the study of cosmic
gamma rays. (Namibia) Name honors Viktor Hess, who received the 1936 Nobel prize for his discovery of cosmic rays.
HET Hobby-Eberly Telescope.(McDonald Observatory)
HETC High Energy Transport Code
HETDEX Hobby-Eberly Telescope Dark Energy Experiment.
HEU Highly Enriched Uranium
Heuristics In computing and artificial intelligence, common sense rules drawn from experience and used to solve problems.
HF High Frequency. Allocated band of radio frequencies from 3MHz to 30 MHz.
HFAG Heavy Flavor Averaging Group.
HFB Hartree-Fock-Bogoliubov
HFBR High-Flux Beam Reactor (Brookhaven)
HFF Heavy Fermion Formalism
HFS HyperFine Structure constant
HGHG High-Gain Harmonic Generation.
HGO Haleakala Gamma Ray Observatory.
HGRF High-Gradient Radio-Frequency.
HGVPU Horizontal Gap Vertical Polarization Undulator
HHCPT Heavy Hadron Chiral Perturbation Theory
HHG High Harmonic Generation
HHLM High-Heat Load Monochromator (LCLS-II-HE)
HHMI Howard Hughes Medical Institute.
HHW Household Hazardous Waste.
HHWR Heating Hot Water Return.
HHWS Heating Hot Water Supply.
HIC Heavy Ions Collision
Hierarchical Routing Routing that is based on a hierarchical addressing scheme. Most Internet routing is based on a two-level hierarchy in
which an Internet address is divided into a network portion and a host portion. Gateways use only the network portion until the datagram
reaches a gateway that can deliver it directly. Subnetting introduces additional levels of hierarchical routing.
HIF Heavy Ion induced Fusion. Also, Heavy Ion Fusion.
Higgs Boson The last particle of the Standard Model, predicted by Peter Higgs, a Scottish theorist. Discovered at the LHC on July 4, 2012.
Higgsino SUSY partner of the elusive Higgs boson.
High Energy Equipment Pool See HEEP.
High Energy Physics See HEP.
High Energy Physics Network See Hepnet.
High Frequency See HF. ENGINEERING
High Voltage Ready See HVR.
High-Level Radioactive Waste See HLW.
HILAC Heavy Ion Linear Accelerator.
HIMAC Heavy-Ion Medical Accelerator in Chiba, Japan. Began operating in 1994.
HIP A program for symbolic calculation of Feynman diagrams.
HIP Holding Ion Pump.
Hi-Potting A troubleshooting technique. The process of increasing a voltage potential to a specified high level, with respect to ground,
in order to check for failure or ground fault in a magnet. Used to measure very high resistances, or the voltage at which an insulator will break down.
HIPPI High Intensity Pulsed Proton Injector (CERN).
HippoDraw A data visualization program for displaying histograms developed by Paul Kunz (SLAC) and Jeff Gould (Gould Software).
HiRes High Resolution Fly's Eye, an experiment.
HIT Heidelberg Ion Therapy centre.
Hitomi X-ray satellite (Japan). Means 'pupil of the eye.'
HIV Human Immunodeficiency Virus.
HIVE HANNA Immersive Visualization Environment (Stanford)
HJ Hamilton-Jacobi
HKT HyperKahler with Torsion
HLA High-Level (physics) Applications. (LCLS)
HLAM Horizontal LAMbertson. A septum magnet used to extract the scavenger beam from the LINAC to the
positron target. Designed by Glen Lambertson. See Septum.
HLS Hydrostatic Leveling System.
HLS Haag-Lopuszanski-Sohnius
HLT High-Level Trigger.
HLW High-Level Radioactive Waste. Waste generated in the fuel of a nuclear reactor and found at nuclear reactors or nuclear fuel reprocessing
plants. It is a serious threat to anyone who comes near the wastes without shielding.
HM Hazardous Materials. (DOE)
HMBP Hazardous Material Business Plan.
HMC Hybrid Monte Carlo
HMP Hazardous Materials Program. (DOE)
HMPID High Momentum Particle Identification Detector (ALICE).
HMSF Hazardous Materials Storage Facility.
HMTA Hazardous Materials Transportation Act. (49 U.S.C. Sec. 1801 et seq)
HOA Hand-Off-Automatic.
HOC Halogenated Organic Compound.
Hodoscope A detector, usually used for triggering and based on scintillation counters with very short output pulses, which records the paths
of ionizing particles by means of ion counters enclose array. (From the Greek pathviewer)
hohlraum In inertial confinement fusion reaction experiments, a gold-lined, pencil-eraser-sized chamber that contains the nuclear energy.
From the German for 'small hollow.'
HOM Higher Order Modes.
Hood Capture Efficiency The emissions from a process which are captured by hood and directed into the control device, expressed as a percent
of all emissions.
Horizontal Lambertson See HLAM.
Host The current computer being used in a network. Also called a server.
Host Name Resolution A mechanism with static and dynamic elements for resolving host names into numeric addresses. The Internet Name Server Protocol
accesses an Internet Name Server which provides dynamic name-to-number translation (this process is specified in IEN 116). The Domain Name Protocol
accesses a Domain name Server which provides dynamic name-to-number translation (this process is specified in RFCs 1033 and 1034). A static local
host table can also be accessed for name-to-number translation.
Host Table An ASCII text file where each line is an entry consisting of one numeric address and one or more names associated with that address.
Host tables are used to resolve host names into numeric addresses.
Hostname The name given to a machine. See also FQDN.
HP Health Physics.
HP Health Physicist.
hPa Hectopascal. 100 Pascals.
HPC High Performance Computing.
HPD Hybrid PhotoDiode
HPF High Performance FORTRAN. An evolving industry standard based on FORTRAN 90 + a FORALL statement + data partition directives that will be
available on IBM's POWERparallel Systems like the 9076 SP1.
HPI Human Performance Improvement.
HPL High Power Laser
HPLC High Performance Liquid Chromatography
HPRF High-Power RF.
HPS Hutch Protection System.
HPS Heavy Photon Search. (experiment)
HPSB High-Performing Sustainable Building.
HPSS High-Performance Storage Systems.
HPT Health Physics Technician.
HPTM High Power Target Module.
HPW Harvard-Pennsylvania-Wisconsin detector.
HPWR High PoWeR.
HQ DOE HeadQuarters (Washington, DC).
HQ High-field Quadrupole.
HQEFT Heavy Quark Effective Theory.
HQET Heavy Quark Effective Theory
HQH Hybrid Quark Hadron.
HR Human Resources Department (SLAC).
HRA High Radiation Area.
HRBP Human Resource Business Partners. (SLAC)
HRD&S Human Resources Development and Services. (SLAC)
HRIS Human Resources Information Systems.
HRMS Human Resources Management System.
HRS Hazard Ranking System. (CERCLA)
HRSC Hoisting and Rigging Safety Committee.
HSA Hazardous Substance Account. A California state fund derived from fees paid by persons who deposit more than 500 pounds per year of
hazardous or extremely hazardous waste to onsite or offsite hazardous waste disposal facilities. This is the primary funding source for the
State Superfund program. (CH&SC Sec. 25300 et seq)
HSD Health and Safety Directive.
HSS Health, Safety and Security office. (DOE)
HST Hubble Space Telescope.
HSWA Hazardous and Solid Waste Amendments. The 1984 law which amended RCRA and created a federal program
for underground tanks.
HTL Hard Thermal Loop
HTM Hierarchical Triangular Mesh.
HTML HyperText Markup Language. The standard language used for creating hypermedia documents within the
World Wide Web. It specifies the layout and linking commands present in the hypertext documents themselves.
HTS High Temperature Superconductivity
HTSC Hartle-Thorne-Sedrakian-Chubarian
HTTP Hypertext Transfer Protocol. The standard application-level protocol for distributed, collaborative, hypermedia information systems. It describes
the way that hypertext documents are fetched over the Internet and is most commonly associated with the World Wide Web.
HUE Historically Under-represented Ethnicities
HUP Hutch User's Panel. (LCLS)
HV High Voltage.
HV Heating and Ventilating unit.
HV t Hooft-Veltman
HVAC Heating, Ventilation and Air Conditioning.
HVR High Voltage Ready. A klystron SDS message indicating that a given klystron is ready for use.
HVTC High Voltage Terminal Cabinet.
HWA Health and Welfare Agency (California).
HWCL Hazardous Waste Control Law. (CH&SC Sec. 25100 et seq)
HWMC Hazardous Waste and Material Coordinator.
HWSA Hazardous Waste Storage Area.
HWSY Hazardous Waste Storage Yard.
HX2 Heat Exchanger 2 (LCLS-II)
HXC Hard X Corrector.
HXRSS Hard X-ray Self-Seeding
Hydrocarbons A large group of organic compounds composed largely of carbon and hydrogen.
Hydrogeology The geology of ground water, with particular emphasis on the chemistry and movement of water.
Hydrology The science dealing with the properties, distribution, and circulation of water.
HYP HYPercubic.
Hyperlink An element in an electronic document that links to another place in the same document, or to an
entirely different document. Typically, you click on the hyperlink to follow the link. Hyperlinks are the most essential ingredient
of all hypertext systems, including the World Wide Web.
hyperon A heavy version of a neutron. Hyperons can be made artificially in accelerators, where they are
unstable and decay quickly.
Hz Hertz. The basic unit of frequency measurement that replaced the former unit of cycles per second (cps).
One hertz is equal to one cycle per second.
Back to top
I The physical symbol that indicates current flow in an electrical circuit.
I/O Input/Output.
IAA Inter-Agency Agreement
IAB Internet Architecture Board. A technical advisory group of the Internet Society, whose responsibilities
include overseeing the Internet Engineering Task Force (IETF) and the Internet Standards process, and publishing and managing
Request for Comments (RFCs).
IACT Imaging Air Cherenkov Telescopes.
IACT The actual current in a magnet displayed by the computer at the last update.
IAEA International Atomic Energy Agency.
IAM Identity and Access Management.
IARC International Agency for Research on Cancer.
IAS Integrated Assessment Schedule.
IAT Initial Acceptance Testing.
iAT it's About Time (SLAC Time & Attendance system).
IATA International Air Transport Association.
IATO Interim Authority to Operate. (DOE)
IBBH Intermediate Binary Black Hole
IBFFM Interacting Boson-Fermion-Fermion Model
IBL Inserted/Insertable B-layer (ATLAS).
IBM Interactive Boson Model
IC Ionization Chamber. A device for detecting ionizing radiation consisting of two high-voltage
electrodes in a gas-filled chamber. The current passing between these electrodes through the ionized gas is proportional to
the level of radiation causing the ionization. It is often used in beam lines
to detect beam loss.
IC Integrated Circuit.
IC Incident Commander.
ICAB Institutional Change Advisory Board.(SLAC)
ICALEPCS International Conference on Accelerator and Large Experimental Physics and Control Systems.
ICAO International Civil Aviation Organization.
ICAP International Computational Accelerator Physics.
ICARUS Imagining Cosmic and Rare Underground Signals (detector, Gran Sasso, Italy)
ICB International Collaboration Board (ILC).
ICC International Code Council.
ICCB Institutional Change Control Board. (SLAC)
ICD Instrumentation and Controls Division (Accelerator Directorate)
ICE Independent Cost Estimate.
ICEC International Cryogenice Engineering Conference.
IceCube A neutrino detector / telescope at the South Pole. .
ICEG International Cryogenic Engineering Conference.
ICET ILC Cost Estimating Tool.
ICFA International Committee for Future Accelerators.
ICHEP International Conference on High Energy Physics.
ICLRT International Center for Lightning Research and Testing.(FL)
ICM IntraCluster Media
ICMP Internet Control Message Protocol. See PING.
ICP Institutional Capital Projects. (SLAC)
ICPT Integrated contractor Purchasing Team. (DOE)
ICR Institutional Cost Report.
ICRP International Commission on Radiological Protection.
ICRU International Commission on Radiation Units and measurements.
ICS Incident Command System.
ICS Inverse Compton Scattering
ICSC International Centre for Scientific Culture.
ICSC International Committee for Science Communication.
ICSM Integrated CyberSecurity Management.
ICSU International Council for Science.
ICUIL International Committee on Ultra-high Intensity Lasers.
ID Inner Detector.
IDAG International Detector Advisory Group. (ILC)
IDE Integrated Development Environment.
IDEAL Inclusion, Diversity, Equity & Access to Learning
IDEAS Initiative to Develop Education through Astronomy and Space science.
IDIQ Indefinite Delivery, Indefinite Quantity (contract).
IDLH Immediately Dangerous to Life and Health. An atmospheric level of a substance which will result in death or irreversible illness
to an individual exposed for more than 30 minutes.
iDM inelastic Dark Matter.
IDP Individual Development Plan.
IDP Internal Dosimetry Program.
IDT Inter-Disciplinary Team.
IE Invert Elevation (with reference to bottom of pipe).
IEEE Institute of Electrical and Electronics Engineers.
IEPM Internet End-to-end Performance Monitoring.
IETF Internet Engineering Task Force. One of the task forces of the IAB. The IETF is responsible for solving short-term engineering
needs of the Internet.
IEWO See IWO
IFC International Fire Code.
IFEFFIT An interactive program for XAFS analysis. (Matt Newville, CARS, University of Chicago).
IFEL Inverse Free Electron Laser
IFI Integrated Facilities and Infrastructure
IFP Initial Financial Plans. (SLAC)
IFR Instrument/instrumented Flux Return.
IFSH Institut fur Friedensfoschung und SicherHeitspolitik (Universitat Hamburg). (Institute for Peace Research and Security Policy).
IFZ Internet-Free Zone.
IG Inspector General.
IGBT Insulated Gate Bipolar Transistor.
IGCC Institute on Global Conflict and Cooperation.
IGEC International Gravitational Event Collaboration (US, Italy, CERN, Australia)
IGES Initial Graphics Exchange Standard.
IGFD Insulin-like Growth Factor Deficiency.
IGM Inter-Galactic Medium
Ignitable Capable of burning or causing a fire.
IGP Interior Gateway Protocol. The generic term applied to any protocol used to propagate network reachability and routing information
within an autonomous system.
IGP Intra-net Gateway Portal. (SLAC)
IGPE Institutional General Purpose Equipment.
IGPP Institutional General Plant Projects. (SLAC)
IGRT Image Guided RadioTherapy.
IH Industrial Hygiene.
IHEM In-House Energy Management.
IHEP Institute for High Energy Physics (Protvino, Russia)
IHEP Institute for High Energy Physics (Beijing, PRC)
IIA Internal Independent Assessment.
IIP Institutional Improvement Plan. A single initiative umbrella prioritizing actions for implementation with three primary areas of focus: safety, WPC, and performance management.
IIP Integrated Interagency Pre-application process. (DOE)
IKE Interactive Klystron Evaluation.
ILC InterLaboratory Collaboration (for R&D towards TeV-scale Electron-Positron Linear Colliders)
ILC International Linear Collider.
ILCSC International Linear Collider Steering Committee (ICFA).
ILCSG International Linear Collider Steering Group.
ILCTA International Linear Collider Test Accelerator (FermiLab).
ILC-TRC International Linear Collider - Technical Review Committee.
ILD International Large Detector concept (ILC). A combination of the former LDC and GLD detector designs.
ILL Institut Laue Langevin. (France)
ILM Integrated Lifecycle Management.
ILT Instructor-Led Training.
IM&PS Information Management and Portal Services. (SLAC)
IMAP Internet Message Access Protocol.
IMCO Intergovernmental Maritime Consultative Organization.
IMDG International Maritime Dangerous Goods Code. (49 CFR)
IMF Intermediate Mass Fragment
Immediately Dangerous to Life and Health level See IDLH.
IMMO 1 min, 1 max, for operating conditions.
IMO International Maritime Organization.
IMP Institute for Modern Physics, of the Chinese Academy of Sciences.
Impoundment A body of water or sludge confined by a dam, dike, floodgate, or other barrier.
IMPT Intensity-Modulated Proton Treatment / Therapy.
IMRT Intensity-Modulated Radiation Treatment.
IMS Intelligent Motion Systems (Inc.)
IMS International Monitoring Systems
ImSim IMage SIMulator. (LSST)
IN2P3 Institut National de Physique Nucleaire et de Physique des Particules (France).
Incineration A treatment technology involving destruction of waste by controlled burning at high temperatures, e.g., burning sludge to
remove the water and reduce the remaining residues to a safe, on-burnable ash which can be disposed of safely on land, in some waters,
or in underground locations.
Incineration Burning of certain types of solid, liquid, or gaseous materials.
Incinerator A furnace for burning wastes under controlled conditions.
INCITE Innovative and Novel Computational Impact on Theory and Experiment program (DOE).
INCREASE INterdisciplinary Consortium for Research and Educational Access in Science and Engineering.
INDU magnetic INDUction.
Indus-1 Electron storage ring, the first synchrotron radiation source designed and developed in India.
Indus-II Synchrotron light source at RRCAT. (India)
INEL Idaho National Engineering Laboratory (now Idaho National Engineering and Environmental Laboratory (INEEL).
Inert Exhibiting no chemical activity, totally unreactive.
INFN Istituto Nazionale di Fisica Nucleare (The Italian National Institute for Nuclear Physics, Frascati)
INFN-CNAF Centro Nazionale per la Ricerca e Sviluppo nelle Tecnologie Informatiche e Telematiche. (the INFN National Center for
Telematics and Informatics)
InGrid An InteGrated micromegas.
Initial Program Load See IPL.
INL Idaho National Laboratory. (DOE)
Inorganic Chemicals A large group of chemicals in which carbon atoms are generally not included, includes oxides, acids, bases, and salts.
INP Institute of Nuclear Problems, of the USSR Academy of Sciences.
INR Institute for Nuclear Research, of the Russian academy of sciences in Moscow.
INSPIRE INvenio plus SPIREs. The next-generation high-energy physics information system. (2008)
INTEGRAL INTERnational Gamma-Ray Astrophysics Laboratory (ESA).
Integrated Services Digital Network See ISDN.
Interaction Point See IP.
Interim Status Allows owners and operators of TSDs that were in existence, or for which construction had commenced, prior to November 19, 1980
to continue to operate without a permit after this date pending final permit issuance. (from RCRA)
Interior Gateway Protocol See IGP.
International Organization for Standardization See ISO.
Internet A decentralized, global network connecting millions of computers worldwide. Each Internet computer, called a host, is independent,
and its operators can choose which Internet services to use and which local services to make available to the global Internet community.
Internet Address A 32-bit address assigned to hosts using TCP/IP.
Internet Number The dotted-quad address used to specify a certain system. The Internet number for the site, cs.widener.edu, is: 147.31.254.130.
A resolver is used to translate between hostnames and Internet addresses.
Interoperate The ability of multi-vendor computers to work together using a common set of protocols.
Interstitial Monitoring The continuous surveillance of the space between the walls of an underground storage tank.
INTGR INTeGRation.
Invar Alloy prized for its resistance to changing shape with changes in temperature.
Inventory TSCA inventory of chemicals produced pursuant to Section 8(b) of the Toxic Substances Control Act.
Inverse barn A barn is a unit of area (10 to the minus 24 centimeters squared) used to measure the chance that something will happen when
two particles collide. An inverse barn is the total number of collisions in a given period of time. Also called integrated luminosity.
IO International Organization.(ITER)
IOC Instrument Operation Center (GLAST).
Ion Chamber See IC.
Ion Gauge See Ionization Gauge.
Ion Pump A type of vacuum pump in which ionized gas molecules are attracted to a cathode by a high voltage where they remain trapped.
IONC See IC.
Ionization Ionization is the process of removing electrons from neutral atoms and thereby producing ions. Because radiation causes ionization,
this effect is often used to detect stray beams in particle accelerators and particle detectors.
Ionization Chamber See IC.
Ionization Gauge A high-accuracy vacuum gauge consisting of a vacuum tube whose emission current is proportional to the density of residual
ions in the volume in which the tube is immersed.
Ionizing Radiation Radiation of sufficiently high energy to cause ionization of the medium through which it passes. Ionizing radiation can
cause extensive damage to biological tissues.
iOS Apple's mobile operating system. (was iPhone OS)
IP Internet Protocol. The network layer protocol for the Internet protocol suite.
IP Inflation Probe.
IP Interaction Point. The point where two beams collide.
IP Implementation Planning. (SLAC Office of Compliance)
IP Ion Pump.
IP / RP Intellectual Property / Research Partnerships (SLAC).
IP Datagram The basic unit of information passed across the Internet. An IP datagram is to the Internet as a hardware packet is to a physical
network. It contains a source and destination address along with data. Large messages are broken down into a sequence of IP datagrams.
IPAC Infrared Processing and Analysis Center (Caltech).
IPAC Intra-Governmental Payment and Collection
IPAM IP Address Management. (Computing)
IPCMS Institute of Physics and Chemistry of Strasbourg.
IPLB Inverse Power Law.
IPM Integrated Performance Management. (DOE)
IPM Intensity Position Monitor.
IPM Ionization Profile Monitor.
IPMC Intelligent Platform Management Controller.
IPMI Intelligent Platform Management Interface.
IPMO Integrated Performance Management Office (SLAC).
IPMU Institute for the Physics and Mathematics of the Universe. Kavli Foundation institute at the University of Tokyo.
IPN Leibniz-Institut für die Pädagokik der Naturwissenschaften und Mathematik. (The Leibniz Institute for Science Education
at the University of Kiel)
IPNS Institute of Particle and Nuclear Science. (KEK)
IPNS Intense Pulse Neutron Source (Argonne)
IPP Institute of Particle Physics (Canada).
IPPP Institute for Particle Physics Phenomenology.(Durham)
IPR Intellectual Property Rights.
IPR Interrupt Pending Register.
IPR Independent Project Review.
IPRP Intellectual Property and Research Partnerships. (SLAC)
IPRV The last recorded current that was within tolerance.
iPS induced Pluripotent Stemcell.
IPT Integrated Project Team.
IPWA energy-Independent Partial-Wave Analysis
IQHE Integer Quantum Hall Effect
IR Interaction Region.
IR InfraRed
IRAS InfraRed Astronomical Satellite
IRB Independent Review Board. (SLAC OCIO)
IRC Infrastructure Review Committee. (SLAC)
IREN Intense Resonance Neutron Source.
IRENG Interaction Region ENGineering design workshop (ILC).
IREP Interactive RadioEpidemiological Program.
IRFs Instrument Response Functions. (GLAST)
Iris The holes on both sides of an accelerator section or RF cavity.
Iris An aperture in an optical system. Profile monitor cameras have adjustable irises to
regulate the light intensity.
iRODS integrated rule based data management system for the data grid.
IRP Integrated Resource Plan (WAPA).
IRR Instrument Readiness Review. (LCLS)
IRTF Infra-Red Telescope Facility. (Hawaii)
IRTF Internet Research Task Force. One of the task forces of the IAB. The group responsible for research and development
of Internet protocol suite.
IS3C Integrated and Sustainable SLAC Scientific Computing.
ISA Industry Standard Architecture.
ISAC Isotope Separator and ACcelerator
ISC Integrated Support Center. (DOE)
ISD Interim Status Document.
ISDC Instrument Science Operations Center. (GLAST)
ISDN Integrated Services Digital Network. An international communication standard for sending voice, video, and
data over telephone lines.
ISEMS Integrated Safety and Environmental Management System.
ISF Israel Science Foundation.
ISGC International Symposium on Grid Computing. (Taipei)
ISGW Isgur-Scora-Grinstein-Wise
ISI Initial State Interaction
ISIS Spallation neutron source at the Rutherford Appleton Laboratory (UK).
ISM Inter-Stellar Matter.
ISM Integrated Safety Management (the concept of the process).
ISMS Integrated Safety Management System (DOE program).
ISO International Organization for Standardization. Coordinator of the main networking standards that are put
into use today.
ISO International Services Office. (SLAC)
ISO Layer One of the seven layers of the International Standards Organization (ISO) Open Systems Interconnection
(OSI) reference model.
ISOC Instrument Science Operations Center.(GLAST)
ISOL Isotope Separator OnLine
Isolated Digital Input Module See IDIM.
Isolated Digital Output Module See IDOM.
ISOLDE On-line radioactive beam source at CERN
ISP Internet Service Provider.
ISPA Imaging Silicon Pixel Array
ISR see CERN ISR
ISR Initial-State Radiation.
ISS Inner Shell Spectroscopy.
ISSC International SKA Steering Committee.
ISSM Integrated Safeguards and Security Management.
ISSP Institute for Solid State Physics.
IT Information Technology
ITAPS Interoperable Technologies for Advanced Petascale Simulations.
ITAR International Traffic in Arms Regulations.
ITEP Institute of Theoretical and Experimental Physics (Moscow)
ITER International fusion experiment aimed at demonstrating the scientific and technological feasibility of fusion energy.
Project partners are China, the European Union, India, Japan, Russia, South Korea and the United States. (Formerly interpreted as
International Thermonuclear Experimental Reactor.)
ITF Injector Test Facility.
ITIL Information Technology Infrastructure Library.
ITPMO Information Technology Project Management Office.
ITPO Innovative Technology Partnership Office.
ITRP International Technology Recommendation Panel (ICFA).
ITRY A magnet parameter indicating the maximum allowed number of tries (or attempts) to trim.
ITSC Information Technology Sub-Council. (SLAC)
ITSR Imaging Techniques with Synchrotron Radiation. (International work shop)
IUA ITER Unit of Account.
IUCF Indiana University Cyclotron Facility.
IUPAP International Union of Pure and Applied Physics.
IV Isolation Vacuum valve (slow), manually operated accelerator valve .
IVA A database polynomial to convert ADC volts to magnet current.
IVBD A function which converts magnet current to B field units when the magnet is on the way down, or being
powered down (derived from magnetic measurements data).
IVBU A function which converts magnet current to B field units when the magnet is being powered up, or the
field is increasing (derived from magnetic measurements data).
IW-BMP Industrial Wastewater - Best Management Plan.
IWO Inter-entity Work Order (DOE)
IWP Israel-Wilson-Perjes
IXAS International X-ray Absorption Society.
IXO International X-ray Observatory.
Back to top
J See PSI.
JAEA Japanese Atomic Energy Agency.
JAERI Japanese Atomic Energy Research Institute.
JAI John Adams Institute for accelerator science. (UK)
JAIDA Java implementation of AIDA - Abstract Interfaces for Data Analysis.
JAPC Java API for Parameter Control.
JAS Java Analysis Studio. Experiment-independent analysis tools for high energy physics data developed
at SLAC.
JASON A US government science advisory group.
Java An object-oriented programming language developed by Sun Microsystems and designed to be small,
simple, and portable across platforms and operating systems. It is best known for its applets, dynamic,
interactive programs that can run inside a World Wide Web page displayed by a Java-capable browser. The
origins of the name 'Java' are explained as: 'It survived the trademark search.'
JavaScript A scripting language developed by Netscape to enable Web authors to design interactive sites.
Although it shares many of the features and structures of the full Java language, it was developed independently.
JavaScript can interact with HTML source code, enabling Web authors to add dynamic content to their sites. It is
supported by most browsers, although Internet Explorer supports only a subset, which Microsoft calls Jscript.
JAXA Japan Aerospace eXploration Agency.
JBD Jordan-Brans-Dicke
JBEI Joint BioEnergy Institute. (DOE)
JC3 Department of Energy Cyber Joint Syberscruity Coordination Center.
JCAE Joint Committee on Atomic Energy (Federal/Congressional)
JCC Joint Committee on Cooperation. Full name: US - USSR Joint Committee on Cooperation and the Peaceful
Uses of Atomic Energy.
JCC FPM Joint Coordinating Committee for research on Fundamental Properties of Matter (US - USSR)
JCCFPM see JCC FPM
JCESR Joint Center for Energy Storage Research.
JCSG Joint Center for Structural Genomics. (SSRL)
JDEM Joint Dark Energy Mission (DOE and NASA). Formerly named Supernova /Acceleration Probe (SNAP) Mission.
JEDI "Juülich Elictric Dipole moment Investigations."
Jefferson Lab The Thomas Jefferson National Accelerator Facility in Newport News, VA, Originally named CEBAF:
Continuous Electron Beam Accelerator Facility. Renamed in May 1996.
JET Joint European Torus (in England)
JFET Junction gate Field-Effect Transistor (also JUGFET)
JGI Joint Genomic Institute.(DOE)
JHAM Job Hazard Analysis and Mitigation.
JHF Japan Hadron Facility
JHP Japan Hadron Project. Proposed multi-instrument facility to be built at KEK in Tsukuba, Japan. Plans
call for a 50 GeV proton synchrotron ring with a diameter of 1500m and a beamcurrent of 10 micro-ampere, a 200 MeV linear
accelerator, and a 3 GeV booster ring. Completion was originally anticipated by 2002, at a cost of about $750 million.
JIMB Joint Initiative for Metrology in Biology (pronounced "Jim Bee")
JINR Joint Institute for Nuclear Research (Dubna, Russia).
JIRA Issue tracking and project management software application.
JL See Jefferson Lab
JLAB Jefferson National Accelerator Facility
JLC Japan Linear Collider.
Joint And Several Liability Under federal and sometimes California law each part that contributed to
damages may be held liable for all damages, but each has the right to compel the others to contribute and indemnify.
JON Judgment Of Need. (DOE)
J-PARC Japan Proton Accelerator Research Complex.
JPEG Joint Photographic Experts Group. Pronounced jay-peg. JPG is a lossy compression technique for
color images. Although it can reduce files sizes to about 5% of their normal size, some detail is lost in the compression.
JPL Jet Propulsion Laboratory (CalTech).
JPS Japanese Physical Society.
JREC Job Requirement and Exposure Checklist.
JSA Job Safety Analyses.
JSC Johnson Spaceflight Center. (NASA)
JSP Java Server Pages.
JSPA Japan's equivalent of the US National Science Foundation.
JSPS Japanese Society for the Promotion of Science.
JWST James Webb Space Telescope.
Jy Jansky. Unit used by radio astronomers for the strength (or flux density) of radio sources. Named in honor of
Karl Guthe Jansky (1905-1950).
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K Kicker magnet.
K Wastes A federal waste category comprised of wastes from specific sources.
K3T K3 - Thurston
KAERI Korea Atomic Energy Research Institute.
KAM Kolmogorov-Arnold-Moser. A theorem stating that oscillatory motions in conservative dynamical systems persist
through the addition of small perturbations to the system.
KAM2 KAMIOKANDE-II underground Cherenkov detector (Tokyo, Japan)
KAMI KAMIOKANDE underground Cherenkov detector (Tokyo, Japan)
KamiokaNDE Kamioka Nucleon Decay Experiment
KamLAND Kamioka Liquid-scintillator AntiNeutrino Detector, located in the Kamioka mine in Japan.
KARMEN Karsruch-Rutherford Medium Energy Neutrino Experiment
KASCADE KArlsruhe Shower Core and Array DEtector.
KAT Komitee für AstroTeilchenphysik. (Committee for Astroparticle Physics, in Germany)
KB Kirkpatrick Baez (mirror system).
k-Band Microwave frequency band extending from 11 GHz to 36 GHz.
Kbps Kilobits per second.
KDD Knowledge Discovery in Databases. (Data mining)
KDP Kemmer-Duffin-Petiau
KDPS Key Decision PointS
KdV Korteweg-de Vries
KEDR The Magnetic Spectrometer Experiment at VEPP-4M (Novosibirsk).
KEK Koo Energy Ken. The High Energy Accelerator Research Organization, Tsukuba, Japan. KEK consists of the Institute
of Particle and Nuclear Studies and the Institute of Materials StructureScience.
KEK PF LINAC KEK electron linac (2.5 GeV) for Photon Factory and TRISTAN.
KEK PS KEK Proton Synchrotron (12 GeV/c Plab).
KEK TRISTAN KEK Tri Ring Intersecting STorage Accelerators at Nippon, an electron-positron storage ring (60 GeV Ecm).
KEKB KEK B-factory. See also B Factory.
Kerberos A network authentication system for use on physically insecure networks, based on the key distribution
model presented by Needham and Schroeder. It allows entities communicating over networks to prove their identity to each
other while preventing eavesdropping or replay attacks.
Kermit A communications protocol that can be used to transfer files or for terminal emulation.
KERN ECDS Surveying and alignment software.
Kernel The level of an operating system or networking system that contains the system-level commands or all of the
functions hidden from the user. In a Unix system, the kernel is a program that contains the device drivers, the memory
management routines, the scheduler, and system calls. This program is always running while the system is operating.
Keybank A chassis that holds eight PPS keys. Keybanks are located outside PPS gates and are used by operators
to: A) monitor and control traffic at the gate, and B) preserve the area PPS status(status cannot be changed if the
keybank is not complete).
KFTC Klystron Fast Time plot Condition.
KG KiloGram.
Kick Kicker magnet.
Kicker A pulsed bend magnet used to kick a beam from its normal path at a precisely predetermined time.
KICP Kavli Institute for Cosmological Physics. (U of Chicago)
KIMS Korea Invisible Mass Search.
KIPAC Kavli Institute for Particle Astrophysics and Cosmology. (SLAC)
Kirk key A special type of key made by Brown Bavarian Kirk. Keys are used with keybanks for Personnel
Protection System (PPS) purposes, or for Power Supply (PS) interlock.
KIT Karlsruhe Institute of Technology.
KK Kaluza-Klein Theory
KKW Keski-vakuri-Kraus-Wilczek.
Klixon A temperature sensor placed on a magnet to shut down the magnet's power supply when the temperature exceeds a given
level. (Klixon is a brand name.)
KLN Kinoshita-Lee-Nauenberg
KLOE Experiment conducted at the Frascati National Laboratories (Italy) phi-meson factory DAFNE
KLT KLystron Temperature. A klystron summary display message indicating that the klystron temperature
is out of tolerance.
KLV KLystron Vacuum. A klystron summary message indicating a fault with the internal klystron vacuum.
KLY See KMD.
KLY KLYstron.
Klystron An electron tube that amplifies microwaves by velocity modulation. A beam of electrons from a hot
cathode is passed through a resonant cavity where it is modulated by high frequency radio waves. The electrons are bunched as
they pass through a final cavity, where they induce RF with a higher gain. The RF from the klystrons is transmitted by rectangular
waveguide to the DLWG of the LINAC.
klystron gallery The narrow building directly above SLAC's two mile linac. It houses the klystrons
which power the linac.
Klystron Phase Requested See KPHR.
Klystron Reflected Energy See RE.
KM Kobayashi-Masakawa.
KM Knowledge Management.
KMB Klystron Magnetic Breaker. A klystron Summary Display message indicating a fault with the electromagnet
circuit breaker that feeds power to the klystron focusing magnet power supply.
KMC Klystron Magnet Current.
KMC A klystron Summary Display indicating a fault with the klystron focusing magnet.
KMD Klystron and Microwave Department.
KMOD The normalized (to energy) field strength of a quadrupole. K stands for curvature and MOD for model.
The KMOD is loaded from a model configuration or is calculated from BDES and the beam energy.
KMS Kubo-Martin-Schwinger
KMST K Minimum Spanning Tree.
KNN K Nearest Neighbor.
KNO Koba-Nielsen-Olesen
KOLR Kolar Gold Field underground detector (India)
Koo Energy Ken See KEK.
KOSEF Korean Science and Engineering Foundation.
KP Kadomtsev-Petviashvili
kPa kiloPascal. 1,000 Pascals.
KPHR Klystron PHase Requested. This is the value sent to the Fox Phase Shifter.
KPI Key Performance Indicator.
KPP Key Performance Parameters.
KPZ Knizhnik-Polyakov-Zamolodchikov
KRF Korean Research Fund.
KSC Kennedy Space Center.
KTIM A magnet parameter and database secondary indicating the last time a magnet was
successfully standardized. See also Standardization.
KTL Klystron Test Lab. (SLAC)
KTLO Keep The Lights On.
kV kiloVolt.
KVI Kernfysisch Versneller Instituut, located in the Netherlands.
KZ Knizhnik-Zamolodchikov
KZB Knizhnik-Zamolodchikov-Bernard
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L Large, Long (abbreviation used in SLAC drawings)
L2SI LCLS-2 Strategic Initiative or LCLS-II Instruments
L3 Detector at LEP (CERN).
LA License Application.
LA Liquid Argon.
LAA Local Administering Agency. (CH&SC Sec. 25500 et seq)
LAA Lepton Asymmetry Analyzer.
LABELIT-CCI Data characterization software for macromolecular crystallography.
LABL Serial number or other label for a magnet.
LABRADOR Large Analog Bandwidth Recorder And Digitizer with Ordered Readout .
LAD License Application Design.
LAER Lowest Achievable Emission Rate. (from CAA)
LAF Linac Accelerator Facility. Includes LCLS-SC, FACET, LCLS-Cu linac areas
LAL Laboratoire de L'Acc'el'rateur Lineare. (Orsay)
LAM Look At Me! A Handshaking protocol between digital electronic systems.
LAMA Library Administration and Management Association.
Lambda CDM Lambda Cold Dark Matter. The leading modern cosmological model.
Lambertson A type of septum magnet named after Glen Lambertson of LBNL. It is used to extract the beam
from the LINAC to the positron target. See also HLAM.
LAMP LCLS-ASG-Michigan Project for novel science with the LCLS FEL.
LAMPF Los Alamos Meson/Proton Factory (1460 MeV/c Plab).
LAN Local Area Network. Any physical network technology that operates at high speed over short distances
(up to a few thousand meters).
Land Ban Informal name for Land Disposal Restricted (LDR).
Landfarming A treatment technique which involves spreading waste on land and utilizing evaporation
and microbial action to degrade the wastes. Used primarily for crude oil wastes. It is not the same as
landfilling.
LANL Los Alamos National Laboratory
LAPP Laboratoire d'Annency-L GOV
LAR Large Adaptive Reflectors.
LAr TPC Liquid Argonne Time Projection Chamber.
Large Power Supply See LGPS.
Large Scale Collaboration Center facility for lab-wide support of science and computing staff with completion
planned in FY2024 (SLAC)
LARP LHC Accelerator Research Program. (US)
Larse A brand name for a general purpose alarm system chassis used at SLAC for monitoring fire alarms.
Laser Light Amplification by Stimulated Emission of radiation. A device that uses the principle of amplification
of electromagnetic waves by stimulated emission of radiation and operates in the infrared, visible, or
ultraviolet region.
Laser Cavity Shutter See LCS.
Laser Feedback Intensity Control See LFIC.
Laser Safety Officer See LSO.
Laser Safety Stopper See LSS.
LASS LASer analyzing Station. A B-line apparatus.
LAST Life, Art, Science, Tech festival
LAT Large Array Telescope (GLAST --FERMI).
LAT Local Area Transport.
LATOR Laser Astrometric Test of Relativity.
Lattice A repeating pattern of magnets.
Launch Knob A multiknob using a set of correctors to launch beam in the LTRs, the Rings or other sections
of the machine. The knobs are orthogonalized to give independent control of position and angle at a given reference point.
LBL Low-energy cut-off BL Lac object.
LBL see LBNL
LBNE Long-Baseline Neutrino Experiment. (FermiLab)
LBNF Long-Baseline Neutrino Facility.
LBNL Lawrence Berkeley National Laboratory, CA. Full name of lab is Ernest Orlando Lawrence Berkeley
National Laboratory.
LC Liquid Crystal.
LC Linear Collider.
LCA Labor Condition Application.
LCA Laser Controlled Area.
LCB Lat Communications Board.
LCC Linear Collider Collaboration. A collaboration between SLAC and KEK to define common parameters for a TeV
center-of-mass energy linear collider.
LCCA Life Cycle Cost Analysis.
LCD Liquid Crystal Display.
LCD Linear Collider Detector.
LCDG4 GEANT4-based flexible full-detector simulation program.
LCFI Linear Collider Flavour Identification Project (ILC).
LCFOA Linear Collider Forum Of America (ILC).
LCFT Logarithmic Conformal Field Theory.
LCG LHC Computing Grid.
LCHb An experiment at the Large Hadron Collider (LHC) to study in detail the physics of the 'b' or 'beauty' quark.
LCID Linac CID.
LCIO Linear Collider Input/Output.
LClo Lethal concentration low. The lowest concentration of a substance in air which has been reported to have
caused death in humans or animals.
LCLS Linac Coherent Light Source. A linac-based X-ray free-electron laser at SLAC.
LCLS-II Linac Coherent Light Source II. next-generation X-ray laser
LCLS-II HE LCLS-II High Energy upgrade
LCPC Laboratory Computer Policy Committee
LCS Laser Compton Scattering.
LCS Laser Cavity Shutter. A PPS device used to stop the PLS laser whenever the laser room door is opened.
LCSGA Linear Collider Steering Group of the Americas.
LCSR Light Cone Sum Rules.
LCTPC Linear Collider Time Projection Chamber collaboration.
LCUK Linear Collider collaboration - United Kingdom (ILC).
LCW Low Conductivity Water. Used for cooling magnets, electrical cables and other devices where normal water could cause a
short under high voltage. LCW is manufactured by deionizing 'house' water at a plant on the SLAC site.
LCWS Linear Collider WorkShop.
LD50 Lethal Dose Fifty. A calculated dose of a substance which is expected to cause the death of 50 percent of an entire defined
experimental animal population.
LDA Local Density Approximation.
LDA Large Aperture Dipoles.
LDAP Lightweight Directory Access Protocol.
LDC Large Detector Concept for the ILC.
LDlo Lethal dose low. The lowest dose of a substance introduced by any route other than inhalation which has been reported
to have caused death in humans or animals.
LDMX Light Dark Matter eXperiment (LCLS-II)
LDR Land Disposal Restricted (Land Ban).
LDRD Laboratory Directed Research and Development. A program to direct the Laboratory's scientific research capabilities
toward vital and emerging scientific challenges that align with the Laboratory's current mission.
LEA Local Enforcement Agency (for solid waste in California).
Leachate A solution of contaminants produced by water flowing through materials such as organic matter,
soil, or landfills.
Lead (Pb) Used extensively at accelerator facilities to shield equipment and personnel from electromagnetic
radiation. A heavy metal that is hazardous to health if breathed or swallowed. Its use in gasoline, paints, and plumbing compounds
has been sharply restricted or eliminated by federal laws and regulations. See also Heavy Metals.
LEAP Low Energy Antiproton Physics, a biennial international conference .
LEAPS League of European Accelerator-based Photon Sources.
LEAR Low Energy Antiproton Ring (CERN)
LEARN Listen, Engage, Assess, Respond, Notice (SLAC)
LEB Low Energy Beam.
LEBT Low-Energy Beam Transport
LeCosPA Leung center for Cosmology and Particle Astrophysics.(Taiwan)
LECT Liquid Effluent Cooling Tank.
LED Light Emitting Diode.
LEE Low Energy Extraction.
LEED Low Energy Electron Diffraction, a popular surface-imaging technique.
LEED Leadership in Energy and Environmental Design (certification from USGBC).
Leed-NC Leed - New construction.
LEEM Low-Energy Electron Microscope.
LEET Large Energy Effective Theory.
LEFF The effective length of a magnet in meters.
LEIR Low-Energy Ion Ring (CERN), formerly LEAR.
LEL Lower Explosive Limit or Lower Flammable Limit (LFL). By percentage, the lowest concentration of a substance
in air which will ignite. Compare UEL and flammability range.
Lemming An operator action which consists of adjusting the LINAC quads to the actual energy of the beam
using the LEM procedure. The computer ascertains the beam energy at each quadrupole from the phases of the klystrons to that point,
and then adjusts the current in each quadrupole for that calculated energy.
LENA Nonmagnetic lead-glass NaI detector at DORIS.
LENS A solenoidal focusing magnet.
Lens Any focusing element.
LEP Large Electron Positron collider (CERN).
LEPC Local Emergency Planning Committee. (from EPCRA)
LER Low Energy Ring in PEP-II, a 3.1 Gev storage ring for positrons.
LESIT LEistungselektronic, Systemtechnik und InformationsTechnologie.
LESIT Low Energy South Injection Transport.
LESR Laser-Electron Storage Ring
LET Low Energy Theorem
Lethal Concentration Low See LClo.
Lethal Dose Fifty See LD50.
Lethal Dose Low See LDlo.
LEUTL Low Energy Undulator Test Line (APS-Argonne).
LFD Light Front Dynamics
LFD Linac & FEL Division (within the Accelerator Directorate)
LFIC Laser Feedback Intensity Control. A feedback system designed to compensate for the loss in laser light intensity of
the PLS. SLAC
LFL See LEL.
LFO Laboratory Financial Operations.
LFTD Light Front Tamm-Dancoff
LFV Lepton-Flavor-Violating/Violation.
LGO Lunar Geoscience Orbiter.
LGT Lattice Gauge Theories
LH2 Liquid Hydrogen.
LHC Large Hadron Collider (CERN).
LHCb Large Hadron Collider beauty experiment. (CERN)
LHT Liquid Hydrogen Targets.
LHW Liquid Hazardous Waste.
LI Abbreviations for Linac.
LIAR LInear Accelerator Research code. Accelerator structure design software.
LIARP LInear Accelerator Research code Parallel. Accelerator structure design software.
LIC Line Item Construction.
Lichtenberg tree Or Lichtenberg Diagram. See Beam Tree.
LIDAR LIght Detection And Ranging
LIGO Laser Interferometer Gravitational-wave Observatory
LIL Linac Injecteur de LEP.
LINAC LINear ACcelerator. A type of particle accelerator in which charged particles are accelerated in a straight
line, either by a steady electrical field or by means of radio frequency electric fields. In the latter variety, the passage of the
particle is synchronized with the phase of the accelerating field. The SLAC LINAC is a two-mile long accelerator, consisting of
cylindrical, disc loaded, copper waveguides placed on concrete girders in a tunnel about 25 feet underground.
LINAC Energy Management See LEM.
Linear Accelerator See LINAC.
Linear Charge Detector See LINQ.
Linear Variable Differential Transformer See LVDT.
LINQ Linear Charge Detector, usually a toroid. `Q' is the physical symbol for electrical charge.
Linux A freely-distributable implementation of UNIX that runs on a number of hardware platforms. It was originally developed
by Linus Torvalds.
LION Long IONization Chamber
Liouville's Theorem The mathematical support to the notion that the area in phase space (emittance) occupied by accelerated
particles is constant.
Liquid Argon Calorimeter See LAC.
LISA Laser Interferometer Space Antenna
LISP LISt Processor. A high-level programming language popular for artificial intelligence applications. LISP was developed in
the early 1960's by John McCarthy at MIT.
List Shorthand term for EPA list of violating facilities or list of firms debarred from obtaining government contracts
because they violated certain sections of the Clean Air or Clean WaterActs. The list is maintained by the Office of Enforcement
and Compliance Monitoring.
Listed Waste Wastes listed as hazardous under RCRA but which have not been subjected to the Toxic Characteristics Listing
Process because the dangers they present are considered self-evident.
Little-endian A format for storage or transmission of binary data in which the least significant byte or bit comes first.
See big-endian.
LJE Liquid Jet End station (LCLS)
LLD Lower Limit of Detection.
LLL See LLNL.
LLM Large Language Model
LLMW Low Level Mixed Waste.
LLNL Lawrence Livermore National Laboratory.
LLO LIGO Livingston Observatory.
LLP Long-Lead Procurement.
LLR Lunar Laser Ranging.
LLRF Low Level Radio Frequency. Also called low level RF. Pertains to controlling the phase and amplitude of RF signals at
low power levels, before they are amplified to high power levels.
LLRW Low-Level Radioactive Waste (ESH)
LLS Synchrotron Light Laboratory (Spain).
LLW Low-Level Waste (ESH)
LMA Large Mixing Angle.
LMC Large Magellanic Cloud.
LMP Lightest Messenger Particle.
LMS Learning Management System. (SLAC)
LN Liquid Nitrogen (tank).
LN2 Liquid Nitrogen
LNF Laboratori Nazionali di Frascati. (INFN)
LNLS Laboratorio Nacional de Luz Sincrotron (Brazil).
LNS INFN Laboratori Nazionali del Sud, Italian laboratory located in Catania.
LNTF Liquid Noble Test Facility
LNW Lehmann-Newton-Wu
LO Leading Order.
LOB Laboratory Operations Board.
LOC Level of Concern. (related to EPCRA)
Local Area Network See LAN.
LODCM Large Offset Double Crystal Monochrometer. Also referred to as LOM (Large Offset Monochrometer).
LOF LAT Operations Facility. (GLAST- FERMI)
LOFAR Low Frequency ARray.
LOI Letters of Intent. (ILC)
LOIS Loss Of Interim Status.
LOLA S-band transverse deflecting structures. Named for creators Greg Loew, Rudy Larsen
and Otto Altenmueller.
LOM Large Offset Monochrometer.
Long Ion Chamber A BCS type beam line device in use in the FFTB tunnel at SLAC. They are gas filled tubes
running parallel to the beam line which are able to detect stray beams using the ionization effect.
Look At Me! See LAM.
LOPA Layer Of Protection Analysis.
LOREA angle-resolved photoemission beamline at ALBA.
LOS Level Of Service.
LOS LockOut Stop.
LOS Laboratory, Office and Shops building (SSRL).
LOSB Laboratory, Office and Shops Building (SSRL).
Lost Phase See LST.
LOTO Lock Out / Tag Out.
Low Conductivity Water See LCW.
Low RF See LRF.
Lower Explosive Limit See LEL.
Lower Flammable Limit See LEL.
LP Laboratory Protection, department.
LPA Large Piwinski Angle.
LPC Laboratory Policy Council.
LPC LHC Physics Center.(Fermilab)
LPC Laser Pulse Chopper.
LPG Liquified Petroleum Gas.
LPHD Local Parton Hadron Duality
LPL Lunar and Planetary Laboratory (University of Arizona).
LPM Landau-Pomeranchuk-Migdal
LPR License Plate Reader.
LPS Leading Proton Spectrometer
LPS Lab Partnering Service (DOE)
LPSPL Low-Power Superconducting Proton Linac.
LQ Long Quadrupole.
LQCD Lattice Quantum ChromoDynamics
LR Long Racetrack.
LRCA Limited Radiological Control Assistant.
LRDP Long-Range Development Plan.
LRF Low RF, A klystron summary display message indicating that the RF power is lower than its normal
tolerance setting.
LRIS Low Resolution Imaging Spectrograph.
LRS Local Rotational Symmetry
LRSM Left-Right Symmetric Model.
LS Level Switch.
LSA Low Specific Activity.
LSBK L-Band Sheet Beam Klystron.
LSC Laser Safety Committee.
LSD Lenses Structure and Dynamics.
LSE Laser Stabilization Experiment.
LSF Load-Sharing Facility. (Computing)
LSH Level Switch High.
LSI Large-Scale Integration.
LSL Level Switch Low.
LSND Liquid Scintillator Neutrino Detector (Los Alamos).
LSO Laser Safety Officer. A person who has authority to monitor and enforce the control of laser hazards.
LSP Lightest Supersymmetric Particle.
LSR Local Standard of Rest. (Astronomy)
LSRA Life Science Research Associate.
LSS Lean Six Sigma (process improvement method).
LSS Laser Safety System. A system of interlocks around a secured enclosure to protect personnel from laser
light.
LSS Large Scale Structure
LSST Legacy Survey of Space and Time (formerly Large Synoptic Survey Telescope).
LSSTC Legacy Survey of Space and Time Corporation (formerly Large Synoptic Survey Telescope Corporation).
LST LoST Phase. A klystron summary status indicating that the PAD is not able to measure the klystron phase.
LST Laser Science and Technology division (LCLS)
LSZ Little String theory.
LTB Lemaitre-Tolman-Bondy
LTB Linac-To-Booster
LTD Low-Temperature Detectors.
LTE Long-Term Exposure (photography)
LTMR Low Temperature Materials Research Group (SLAC)
LTR Low Temperature Materials Research.
LTR Low Temperature Reservoir.
LTU Linac-To-Undulator.
Lucretia A physics toolbox for the simulation of high-performance single-pass electron beam transport systems.
LUFT Leaking Underground Fuel Tank.
Luminosity A measure of the number of events per second and per unit cross section at the IP.
LUSI LCLS Ultrafast Science Instrument Project.
LUST Leaking Underground Storage Tank.
LUX Large Underground Xenon dark matter experiment.
LVD Large Volume Detector (Gran Sasso)
LVDT Linear Variable Differential Transformer. A device for measuring positions relative to a fixed reference,
(e.g., for measuring slit positions).
LVV Limited Visibility Vehicle.
LWBM Lab-Wide Budget Model
LWC Lost Work Cases.
LWFA Laser WakeField Acceleration
LZ LUX-ZEPLIN detector. (South Dakota)
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M&O Management and Operations.
M&S Materials and Supplies.
M13 Messier 13
MA Magnetic Alloy
MAC Macintosh computer.
MAC Machine Advisory Committee. (ILC)
MAC Moves, Adds, Changes. (Telecommunications)
MAC Most Attractive Channel
MACHe3 MAtrix of Cells of superfluid 3He.
Machine Protection System See MPS.
MACHO MAssive Compact Halo Object, or Massive Astrophysical Compact Halo Object
MACRO A sequence of keyboard or touch panel operations created and saved to be initiated by one keystroke as an Operator
aid. Also, a user- defined abbreviation for one or more lines of code.
MACRO Monopole, Astrophysics and Cosmic Ray Observatory
MacSamson A file transfer and terminal emulation program that allows a Macintosh to be used as a terminal for
a host computer.
MAD Multiple wavelength Anomalous Dispersion phasing. A primary means of solving
protein structures.
MAD Methodical Accelerator Design. A data input format for TRANSPORT.
MAGIC Major Atmospheric Gamma Imaging Cherenkov Telescope, on the Canary Island of La Palma. Mail Gateway A machine that connects to two or more electronic mail systems (especially dissimilar mail systems
on two different networks) and transfers mail messages among them. Mailing List A discussion group, sometimes moderated, whose messages are distributed via e-mail from
a central computer which maintains the list of people involved in the discussion.
Main Beam Containment Unit See MBCU.
Main Control Center See MCC.
Main Drive Line See MDL.
Main Manifold Controller A chassis monitoring the vacuum level of a system.
Majordomo A free mailing list server that runs under UNIX. When e-mail is addressed to a Majordomo mailing list, it is
automatically re-broadcast to everyone on the list. The result is similar to a newsgroup or forum, except that the messages are
transmitted as e-mail and are therefore available only to the individuals on the list.
MAN Metropolitan Area Network. (DOE - SF Bay Area)
Management Information System See MIS.
Manhist Program for MANipulating HISTograms. C
Manifest Form which indicates generator, quantity, type of waste, and disposer of waste for each shipment of hazardous
wastes sent to offsite facilities.
MAP Management Assessment Program. (SLAC)
MAPS Monolithic Active Pixel Sensor. HEP
Marx Modulator An electrical circuit designed to generate a high voltage impulse. Named for Edwin Otto Marx, who first
described such a circuit in 1924.
Mask A collimator used to shelter a detector from synchrotron radiation or other low-energy radiation. It is also used
to protect detector components from direct hits by an errant beam.
Mass Spectrometer See Spectrometer.
Master Oscillator The oscillator generating the RF distributed by the MDL to the whole LINAC. The frequency is
476 MHz (the 6th subharmonic of the 2856 MHz LINAC klystron frequency).
Master Pattern Generator Zero See MP00.
Master Trigger Generator See MTG.
Material Safety Data Sheet See SDS.
MATLAB A matrix manipulation software package for computation and plotting.
Matrox Board A hardware interface card, made by the Matrox Corporation, used to drive video display monitors. For example,
a scrolling graphic display of both beams showing the energy and current as transmitted to MCC by the Micro FB31 from BPMs
reading in a dispersion region in the arcs.
MAX II Storage ring for electrons at MAX-lab, Lund University, Sweden.
MAX IV Storage ring facility at MaxLab in Lund, Sweden inaugurated June 2016.
MB See Megabyte.
MB Maxwell-Bozmann
MBAM Microsoft Bitlocker Administration and Monitoring.
MBCU Main Beam Containment Unit. An interlock chassis at NPI and CID for use by the beam containment system for wide
pulse beams.
MBE Multiple beam experiment
MBE Molecular Beam Expitaxy PHYSICS
MBH Massive Black Hole.
MBI MicroBunching Instability.
MBK Multi-Beam Klystron.
MBps MegaBytes per second.
MBR Molecular Beam Resonance technique.
MBTS Minimum Bias Trigger Scintillators. (LHC)
MC Monte Carlo. See Monte Carlo Method.
MC Mode Converter
MC Macromolecular Crystallography
MCC Motor Control Center.
MCC Merchant Category Code.
MCi MegaCurie. ENVIRO
MCIC The Metals and Ceramics Center (Columbus, OH).
MCL Maximum Contaminant Level.
MCL Maximum Concentration Level
MCMC Markov Chain Monte Carlo
MCNP Monte Carlo simulation package (LANL).
MCP Major Capital Project.
MCR Methyl-Coenzyme M Reductase.
MCRG Monte Carlo Renormalization Group
McT McCallum-Turner, Inc.
MD Management Directive.
MD Mechanical Design. Department (SLAC).
MD Manual Damper.
MD1 Magnetic detector at VEEP-4, Novosibirsk
MDA Minimum Detectable Activity.
MDH4 MoDe Hutch 4. Also, MDH5, MoDe Hutch5. Aligns control of stoppers to the
hutch taking beam. PHOTON
MDI Machine Detector Interface.
MDL Main Drive Line. A temperature-stabilized coaxial cable which carries the 476 MHz master oscillator signal, and
a fiducial synchronizing signal used to unify timing of the klystrons in the LINAC and to trigger the PDUs. The length
of the MDL is monitored by an interferometer, since changes in its length due to thermal changes will result in klystron
phase changes down the LINAC.
MDM Mobile Device Management.(OCIO)
MDM Mixed Dark Matter
MDOT MicroDOT gas chambers
MDP Markov Decision Process.
MDRP Millikan DRoP measurement.
MDT Monitored Drift Tubes.
ME Mechanical Engineering. Department (SLAC).
ME2 see MEE.
MEA Medium-Energy Accelerator.
MEC Mission Executive Council.
MEC Matter in Extreme Conditions or Material at Extreme Conditions.
Mechanical Design See MD.
Mechanical Engineering See ME.
MECi Matter in Extreme Conditions instrument. (LCLS)
MECL Motorola Emitter Coupled Logic. An integrated circuit technology used for fast logic boards.
MECO Muon-to-Electron COnversion.
MED Mechanical Engineering and Design. (SLAC)
MED Medical Department.
Medium The material used to support the transmission of data. This can be copper wire, coaxial cable, optical fiber,
or electromagnetic wave (as in microwave).
MEDSI Mechanical Engineering Design of Synchrotron radiation equipment and Instrumentation.
MEE Materials in Extreme Environments. (LCLS)
Megabyte 1,048,576 bytes or 1,000 kilobytes, roughly one million bytes or one thousand kilobytes.
Mega-Czar Term used to designate person within a group who has responsibility for administration of a type of
information resource, and who is authorized to appoint other czars within their computing group. See also czar.
Mega-Electron-Volt See MeV.
Megaflops One million floating-point operations per second. Abbreviated MFLOPS.
MEIS Molecular Environmental Interface Science.
Melting Point See MP.
MEM Maximum Entropy Method.
Memorandum of Understanding See MOU.
MEMS MicroElectroMechanical Systems.
MES Molecular Environmental Sciences. A discipline which uses synchrotron-based spectroscopic techniques to study
environmental problems.
MESH Microfulidic Electrokinetic Sample Holder.
MESI Mechanical Engineering Safety Inspection.
MET METallographic.
MET Metrology Department (SLAC)
Meta Data Data about data. In an electronic environment, meta data's basic elements are a structured format and a
controlled vocabulary, which together allow for a precise description of a digital entity's content, location,
and value.
Meter Relay A Beam Containment module which looks at a magnet power supply to require that its voltage, as read
on the meter, be inside or outside some set points. See also Beam Containment System.
Method 18 An EPA test method which uses gas chromatographic techniques to measure the concentration of individual
volatile organic compounds in a gas stream.
Method 24 An EPA reference method to determine density, water content, and total volatile content (water and VOC)
of coatings.
Method 25 An EPA reference method to determine the VOC concentration in a gas stream.
METSD Mechanical Engineering and Technical Support Division.
MeV Mega-Electron-Volt. 1 Million eV. The LINAC klystrons accelerate the beam approximately
200 MeV per station.
Mev-UED Mega Electron Volt Ultrafast Electron Diffraction instrument (LCLS)
MEWP Mobile Elevated Work Platform. Work surface higher than four feet, e.g.
scissors lift or articulating boom lift
MEXT Ministry of Education, Sports, Science and Technology (Japan).
MFA Multi-Factor Authentication.
MFD Mechanical Fabrication Department.
MFD Multi-Function Device
MFD Mechanical Fabrication Department.
MFD Mechanical Facilities Department.
MFENET Magnetic Fusion Energy NETwork. It is centered at the Lawrence Livermore Lab.
MFG ManuFacturinG.
MFM Magnetic Force Microscopy.
MFT Managed File Transfer.
MFX Macromolecular Femtosecond (X)crystallography.
MGC Microgap Gas Chambers
mgd Million gallons per day.
MHD MagnetoHydroDynamics
MHS Message Handling System. The system of message user agents, message transfer agents, message stores, and access units
which together provide OSI electronic mail.
MHz MegaHertz.
MICADO A steering algorithm meaning in French `MInimisation des CArres des Distortions d'Orbite' which translates to
Minimization of the squares of the orbit distortion. One of several methods used by the orbit correction
programs at SLAC.
Microbial Action Using the action of microbes to destroy or transform compounds.
Micromegas MICRO-MEsh GASeous detector.
MIE Major Items of Equipment.
Mie A scattering spectroscopy used to study changes in the size and index of refraction of spherical and
non-spherical particles whose size is within a factor of 10 from the light's wavelength. (SLAC-R -611)
Million Instructions Per Second See MIPS.
MILNET MILtary NETwork. Originally part of the ARPANET, MILNET was partitioned in 1984 to make it possible for
military installations to have reliable network service, while the ARPANET continued to be used for research.
MIL-SPEC MILitary SPECifications.
MIME Multipurpose Internet Mail Extensions. A way to attach any kind of file to an e-mail message. Supersedes uuencoding
in newer Unix e-mail systems.
MIN MINute.
MinSec Minimum Security requirements (computing)
MIPS Million Instructions Per Second. Refers to the average number of machine language instructions a computer performs
in one second.
MIRAS Infrared microspectroscopy beamline at ALBA.
MIRI Mid InfraRed Instrument. (JWST)
MIS Management Information System. A formal network that extends computer use beyond routine reporting and into the
area of management decision-making. Its goal is to provide the correct information to the appropriate manager at the
right time.
MIT Massachusetts Institute of Technology
Mitigation Measures taken to reduce adverse impacts on the environment.
MITOMI Mechanically Induced Trapping of Molecular Interactions.
MJ MegaJoule
MKB MultiKnoB. An operator station knob moving the field, the timing, or the phase of more than one device at
the same time.
mKdV modified Korteweg-de Vries
MKN Maung-Kahana-Norbury.
ML Machine Learning
ML Microwave Lab (Stanford)
MLE Maximum Likelihood Estimate.
MLEV Magnetic LEVitation.
MLLA Modified Leading Log Approximation
MLLW Mixed Low Level Waste.
MLVR Medium and Low Voltage Revitalization
MMC see Main Manifold Controller.
MMF Magnetic Measurement Facility (B081)
MMGC Main Manifold Gauge Controller. A special gauge (one per sector) which senses vacuum for an entire sector. In
the event of a vacuum leak, the MMGC sends two signals: one to the TIU, which interrupts the beam in the injector and
one to the Fast Valve Controllers, whose valves seal and isolate that Sector from the rest of the accelerator.
MMI Maintenance Management Index.
MMIC Monolithic Microwave Integrated Circuit.
MMNTM MoMeNTuM.
MMS Missing Mass Spectrometer.
MMX Matrixed Mfd technicians for X-ray operations.
MNS Maki-Nakagawa-Sakata.
MOA Memorandum of Agreement
MOC Mission Operations Center (GLAST).
MOCVD Metal-Organic Chemical Vapor Deposition.
MOD MODel.
Modulation A method used in modems to make data processing signals compatible with
communication facilities.
MoEDAL Monopole and Exotics Detector At the Large hadron collider.
MOJAVE Monitoring Of Jets in Active galactic nuclei with VLBA Experiments . (US and Europe)
Moller Polarimeter A device used to detect the degree of polarization of electrons by using a polarized target
and the Moller effect.
Moller Scattering An elastic collision between two electrons.
MOM Momentum
MoNA Modular Neutron Array. (NSCL)
MONALISA MONitoring Agents in a Large Integrated Services Architecture.
MONALISA MONitoring ALIgnment and Stabilization with high Accuracy. (AFT2 system).
MONARC Models of Networked Analysis at Regional Centres. LHC computing project.
MOND MOdified Newtonian Dynamics.
MONO MONOchromator. (LCLS)
Monte Carlo method A method of computer simulation that allows scientists to assess probable outcomes of
experiments or events. The method employs repeated simulations of an event using actual data, where known, and
providing probable values of unknown data. Probable values of unknown data are selected anew for each simulation
by a random number generator. Based on the Metropolis Algorithm (1946).
MORSE-CG Multipurpose neutron and photon transport code.
MORTRAN A FORTRAN precompiler.
MOS Metal On Silicon.
MOSG Maintenance Operations Support Group. A SLAC operational group.
MOSS Microsoft Office Sharepoint Server 2007.
MOST Ministry of Sciences & Technology. (China).
MOT MagnetOptic Trap. A combination of laser cooling using a web of laser beams and magnetic cooling using a
web of magnetic fields. The web of laser beams cools atoms by bombarding them from many directions, and the web of
magnetic fields induces evaporative cooling by encouraging warmer atoms to depart. Cooler atoms coalesce in the
trap to form a Bose-Einstein condensate (BEC).
Motif A GUI based on X Windows and distributed by the Open Software Foundation.
Motorola Emitter Coupled Logic See MECL.
MOU Memorandum of Understanding. Used by CDHS to formalize agreement between themselves and local programs
with regard to enforcement of the HWCL.
MOX Mixed-Oxide Fuels.
MP Melting Point. The temperature at which the solid and liquid forms of a substance exist in equilibrium.
Mpc megaparsec. One million parsecs.
MPDC Multi-Purpose Data Center.
MPE Maximum Permissible Exposure.
MPF Microlensing Planet Finder. (Proposed)
MPG Master Pattern Generator. See also MP00.
MPGD Micro-Pattern Gas Detector.
MPIfR Max-Planck-Institut fur Radioastronomie.
MPP Massively Parallel Processors. For example, IBM's 9076 SP1, Thinking Machines' CM-2, and Intel's Touchstone
Gamma computers.
MPPC Multi-Pixel Photon Counter.
mppcf Millions of particles per cubic foot of air.
MPRSA Marine Protection, Research, and Sanctuaries Act. (Federal)
MPS MultiParticle Spectrometer (BNL).
MPS Machine Protection System. A system to protect the machine from damage from the beam. It uses ionization
chambers, current monitors, temperature detectors, and microswitches on valves and other obstructions to rate-limit
or turn off the beam whenever necessary.
MPS2 MultiParticle Spectrometer upgrade (BNL).
MPSF MultiParticle Spectrometer at Fermilab.
MPWA Model-dependent Partial-Wave Analysis
MQCD M theory QCD
mQs Millicharged particles
MR Main Ring
MRCOFFEE Multi-Resolution "Cookiebox" Optimized for the Future of Free-Electron (laser)
Experiments
MRD Monthly Reporting Database. (SLAC)
MRE Meal, Ready-to-Eat (U.S. Government)
Mrem Milli Rad Equivalent Man.
MRFM Magnetic Resonance Force Microscopy.
MRI Magnetic Resonance Imaging.
MRL Minimum Reporting Level.
MRS Monitored Retrievable Storage.
MRS Magnetic Resonance Spectrometer
MRS Materials Research Society.
MRS Metal-Resistive layer-Silicon photodetector
MRST Martin-Roberts-Stirling-Thorne
MS Member States (CERN).
MS Minimal Subtraction
MS Manual Station. A manually activated fire alarm sensor.
MS Management Systems
MSAM Medium Scale Anisotropy Measurement
MSD Materials Science Division (SSRL)
MSDS Material Safety Data Sheet. An industry standard form used for listing and describing hazardous
chemicals. Named changed to Safety Data Sheet (SDS).
MSE Materials Sciences and Engineering Division (DOE)
MSG Mechanical Services and maintenance Group. (SSRL)
MSGC MicroStrip Gas Chamber.
MSHA Mine Safety and Health Administration.
MSI MicroSoft Installer.
MSIS Management Systems Improvement Strategy.
MSL Multilayer Soft Lithography.
MSL Mars Science Laboratory. (NASA)
MSM Minimal Standard Model
MSO Management System Owner.
MSPB Merit Systems Protection Board.
MSPs MilliSecond Pulsars.
MSSM Minimal Supersymmetric Standard Model
MSTR MicroSTRategy (software).
MSW Mikheev-Smirnov-Wolfenstein
MT Magic Tee.
MTA Message Transfer Agent. An OSI application process used to store and forward messages in the X.400
Message Handling System. Equivalent to an Internet mail agent.
MTB Materials Transportation Bureau. A subdivision of DOT.
MTBF Mean Time Between Failures. Average time a device will function before failing.
mTCA micro Telecommunications Computing Architecture.
MTEU Master Terminal Expander Unit. A fire alarm chassis from LARSE.
M-Theory Posits that the strong-coupling behavior of supersymmetric string theories and field theories
is governed by a web of dualities relating the different theories. This web is called M for magic, mystery, and / or membrane.
MTL Main Test Level.
MTTF Mean Time To Failure.
MTU Maximum Transmission Unit. The largest possible unit of data that can be sent on a given physical medium. For
example, the MTU of Ethernet is 1500 bytes.
MTU Master Terminal Unit. A fire alarm chassis from LARSE.
MU Mechanical Utilities.
Mu2e Muon to electron conversion experiment. (Fermilab)
Multiknob See MKB.
Multiple Clip A PPS locking device which allows multiple users to lock a breaker in order to service some piece of
equipment. This ensures that no one will energize the breaker while another group is still working on the equipment
it powers. All locks on the multiple clip must be removed before the breaker can be energized.
Multiplex The division of a single transmission medium into multiple logical channels supporting many apparently
simultaneous sessions.
Muon A lepton with the same charge as the electron, but with mass 210 times larger, and a lifetime of 2.2 microseconds.
Because muons interact only electromagnetically, they are very penetrating. Shielding the detector from spurious muon
radiation requires massive shielding. Muons were discovered in cosmic rays by C. F. Powell at Bristol in 1947.
MUSYC MUltiwavelength Survey by Yale and Chile.
Mutagenic Capable of causing changes in the genetic code by altering DNA.
Mutate To bring about a change in the genetic constitution of a cell by altering its DNA. In turn, `mutagenesis' is
any process by which cells are mutated.
MV McLerran-Venugopalan
MVC Model View Controller.
MW MegaWatt
MWA Management Walk-Around (SLAC)
MWH MegaWatt-Hours.
MWPC MultiWire Proportional Chamber.
MWTC Multiscale Walking TechniColor
MXL The name of a cerberus pyrotronics control panel. The term is also used at SLAC to designate the fire
detection system.
MYRRHA Multipurpose hYbrid Research Reactor for High-tech Applications. ( Planned facility in Belgium)
Back to top
N&S Necessary and Sufficient (ES&H).
n. o. s. Not otherwise specified. (from 49 CFR)
NA Nucleon area
NA Code North American Code. (from 49 CFR)
NAA NonAttainment Area (from CAA). An area whose ambient air levels exceed federal or
state standards.
NAAQS National Ambient Air Quality Standards. (from CAA)
NACA National Advisory Committee for Aeronautics.
NACE National Association of Corrosion Engineers.
NAE National Academy of Engineering
NAG Numerical Algorithms Group
NAL National Accelerator Laboratory (FermiLab). See also FNAL
NALCD North American Linear Collider Detector
NALTA North American Large-scale Time-coincidence Array.
NAMASTE Next generation Atomic, Molecular, and Accelerator Science and Technology
Experiments (LCLS)
Named Pipes A reliable form of interprocess communication in which a direct link is established by a server
for a client.
nanoPE nanoporous PolyEthylene.
NARA National Archives and Records Administration.
Narrow Pulse Generator See NPG.
NAS National Academy of Sciences.
NAS Network Attached Storage
NASA National Aeronautics and Space Administration
NASA/GSFC National Aeronautics and Space Administration/Goddard Space Flight Center.
National Environmental Policy Act See NEPA.
NB Negative Binomial
NBD Negative binomial distribution
NC Neutral Current
NCA Network Computing Architecture.
NCG NonCommutative Geometry
NCI National Cancer Institute.
NCI Nuclear Control Institute (non-proliferation research), Washington D.C.
NCI Nuclear Cities Initiative
NCM NEPA Compliance Manager.
NCOS NonCommutative Open String theory.
NCP National Contingency Plan.
NCQFT Non-Commutatitive Quantum Field Theories.
NCRP National Council on Radiation Protection.
NCRR National Center for Research Resources (National Institutes of Health).
NCS National Communications System.
NCSA National Center for Supercomputing Applications. A federally-funded organization whose mission is to
develop and research high-technology resources for the scientific community.(Illinois).
NCSC National Computer Security Center.
NCXT National Center for X-ray Tomography (ALS).
NCYM NonCommutative Yang-Mills.
ND NaI detector at VEPP-2M, Novosibirsk.
NDA Non-Disclosure Agreement.
NDBD Neutrinoless Double Beta Decay
NDE Non-Destructive Examination.
NDIM Negative Dimensional Integration Method
NDMS National Disaster Medical System.
NDR Naive Dimensional Regularization
NDT Non-Destructive Testing
NE Nuclear Experiment.
NEA Near-Earth Asteroid.
NEAC Nuclear Energy Advisory Committee (DOE) GOV
NEC National Electrical Code.
NECA National Electrical Code Association.
NEG Non-Evaporable Getter (pump).
NEH Near Experimental Hall. (LCLS) PHOTON
NEHA National Environmental Health Association. See also CHWS.
NEIC National Enforcement Investigations Center. A subdivision of EPA.
NEMA National Electrical Manufacturers Association.
NEO Near-Earth Objects.
NEO New Employee Orientation. (SLAC)
Neoparadoxia Repenningi A member of a small family of large, herbivorous marine mammals that inhabited the northern
Pacific coastal region during the Miocene epoch (20 to 10 million years ago). A fossil skeleton was unearthed at SLAC
in October 1964, during the excavation for the linear accelerator beam switchyard. Originally called paleoparadoxia,
it was reclassified in 2013.
NEPA National Environmental Policy Act. The 1969 federal act which created the requirement for an Environmental
Impact Statement for projects involving federal funding.
NERAC Nuclear Energy Research Advisory Committee (DOE). See NEAC.
NERSC National Energy Research Scientific Computing Center. (DOE)
NESHAP National Emission Standards for Hazardous Air Pollutants. (from CAA)
NEST Nuclear Emergency Search Team.
NESTOR Neutrino Extended Submarine Telescope with Oceanographic Research. (Greece).
NetBEUI NetBIOS Enhanced User Interface. An interprocess communications standard developed by IBM. NetBEUI provides
network interfaces used by a network operating system (which operates at the presentation layer) to access the session
layer of the ISO model. As defined by IBM.
NetBIOS Network Basic Input/Output Subsystem. An interprocess communications standard developed by IBM. NetBIOS provides
network interfaces used by a network operating system (which operates at the presentation layer) to access the session
layer of the ISO model.
NetBIOS Enhanced User Interface See NetBEUI.
NETC National Emergency Training Center.
NETL National Energy Technology Laboratory. (DOE)
Network A group of machines connected together so they can transmit information to one another. There are two kinds
of networks: local networks and remote networks.
Network Address 1) The physical or hardware address of a network interface card. For Ethernet this 48-bit address
might be 0260.8C00.7666. The hardware address is used to forward packets within physical network. 2) The logical
or Internet address is used to facilitate moving data between physical networks. The 32-bit Internet address is
made up of a network number, a subnetwork number, and a host number. Each host computer on the Internet has a
unique address. All Internet addresses at SLAC have a network number of 134.79. All Internet hosts have a
numeric address and an English-style name. For example, the Internet address for SLAC's IBM 3480 is
134.79.17.41. Its Internet name is SLAC.Stanford.EDU.
Network Basic Input/Output Subsystem See NetBIOS.
Network Operating System See NOS.
NEUL NEULand large-angle neutrino spectrometer.
NEXAFS Near Edge X-ray Absorption Fine Structure.
nEXO next-generation Enriched Xenon Observatory.
NFC Natural Flavor Conserving
NFPA National Fire Protection Association.
NFPA No Fixed Point Automorphisms
NFS Network File System. Protocols developed by Sun Microsystems to allow access to remote files as if they
were local. Originally written for Unix but expanded to include PC, MAC and other systems. See also: AFS
NGC New General Catalog of nebulae and star clusters. (Dreyer, Memoirs of the RAS V49, N.1)
NGLS Next Generation Light Source. (LBNL)
NGS Neutrino beam to Gran Sasso
NGST Next Generation Space Telescope
NGT Nonsymmetric Gravitational Theory
NHZ Nominal Hazard Zone.
NIC The Network Information Center. There are many NICs operated by local, regional, and national networks
all over the world. Such centers provide user assistance, document service, and training.
NICADD Northern Illinois Center for Accelerator and Detector Development.
NICE Serpukhov nonmagnetic precision spectrometer.
NICER Neutron star Interior Composition Explorer. (NASA)
NIEHS National Institute of Environmental Health Sciences.
NIF National Ignition Facility (LLNL).
NIGMS NIH Institute for General Medical Sciences.
NIH National Institutes of Health.
Nikhef Nationaal Instituut voor Kernfysica en Hoge-Energie Fysica (Amsterdam). As of 1998, renamed National Institute
for Subatomic Physics (Nikhef is no longer an acronym)
NIM Normal Incidence Monochromator SSRL
NIOSH National Institute for Occupational Safety and Health.
NIRCam Near InfraRed Camera. (JWST)
NIRNS National Institute for Research in Nuclear Science.
NIRSpec Near InfraRed Spectrograph. (JWST)
NIS Network Information System. A database containing the user names, machine names, and directory names that a
Network File System uses to track all machines on a network. Formerly called 'Yellow Pages' (yp).
NIS Network Information Service (Sun). Major components include the ypserv and ypbind daemons started at boot
time in the /etc/rc.local script, these daemons handle NIS database communications for both servers and clients.
NIST National Institute of Standards and Technology.
NISUS Near-Infrared Scalable Undulator System.
NJL Nambu-Jona-Lasinio
NLA Next-to-leading Logarithmic Approximation.
NLCTA Next Linear Collider Test Accelerator. A SLAC prototype of a short section of the proposed ILC. SLAC
NLDC National Laboratory Directors' Council.
NLL Next-to-leading Logarithmic Level
NLLA Next-to-Leading Logarithmic Approximation
NLO Next-to-Leading Order
NLS Nonlinear Schrodinger
NLSP Next Lightest Supersymmetric Particle
NMC Nickel Manganese Cobalt oxide.
NMC New Muon Collaboration
NMC Next Muon Collider
NMI NSF Middleware Initiative.
NMI Non-Maskable Interrupt.
NML New Muon Lab (Fermilab)
NMR Nuclear magnetic resonance.
NMS Network Management Station. The system responsible for managing a portion of a network. The NMS talks to
network management agents, which reside in the managed nodes, via a network management protocol.
NMSSM Next to Minimal Supersymmetric Standard Model
NNAC Nonproliferation and National Security Advisory Committee (DOE)
NNI Nearest Neighbor Interaction
NNLL Next-to-Next-to-Leading Logarithmic.
NNLO Next-to-Next-to-Leading Order.
NNMI National Network for Manufacturing and Innovation.
NNSA National Nuclear Security Administration. (DOE)
NNSAC Non-proliferation and National Security Advisory Committee. Also known as NNSA. GOV
NO NonOscillatory
No Observed Effect Level See NOEL.
NOA Notice Of Award. (Stanford)
NOAA National Oceanic and Atmospheric Administration
NOAEL No Observed Adverse Effect Level.
NOAO National Optical Astronomical Observatory. (NSF)
Node Any computer, terminal or peripheral on a network. It is also called a host.
NOEL No Observed Effect Level. The highest dose in an animal toxicity study for which no effect was observed.
NOI Notice Of Intent or Inquiry.
Nonattainment Area See NAA.
Non-ionizing Electromagnetic Radiation Radiation that does not change the structure of atoms but does heat tissue
and may cause harmful biological effects. Sources include laser light, microwaves, radio waves, and low-frequency
electromagnetic fields from high-voltage transmission lines.
NOPR Notice of Public Ruling.
NORM Naturally Occurring Radioactive Material.
NOS Network Operating System. An operating system specifically designed to manage and control a network or
networks and related services.
NOvA NuMi Off-axis ve (electron neutrino) Appearance experiment.
NOVO VEPP 2M NOVOsibirsk VEPP-2M electron-positron storage ring (1.4 GeV Ecm).
NOVO VEPP 4 NOVOsibirsk VEPP-4 electron-positron storage ring (14 GeV Ecm).
NP Noteworthy Practice.
NP New Physics.
NPACI National Partnership for Advanced Computational Infrastructure.
NPAS Nuclear Physics At SLAC.
NPDES National Pollutant Discharge Elimination System. (from CWA)
NPG Narrow Pulse Generator. A test module used to simulate beam pulses for diagnostic purposes.
NPRCS No-Permit-Required Confined Space.
NPS See NPAS.
NPSS Nuclear and Plasma Sciences Society (IEEE).
NQIAC National Quantum Initiative Advisory Committee
NR Non-Rotatable (flanges)
NRAO National Radio Astronomy Laboratory.
NRC Nuclear Regulatory Commission.
NRC National Response Center.
NRC National Research Council, in Washington D.C.
NRDC Natural Resources Defense Council.
NREL National Renewable Energy Laboratory. (DOE)
NREN National Research and Education Network.
NRL Naval Research Laboratory (US)
NRQCD NonRelativistic QCD
NRQED NonRelativistic QED
NRT National Response Team.
NRTL Nationally Recognized Testing Laboratory.
NRY North Research Yard.
ns nanosecond
NS Neveu-Schwarz
NSA National Security Agency.
NSAC Nuclear Science Advisory Committee (DOE)
NSC Nanoscience Safety Committee. (SLAC)
NSCL National Superconducting Cyclotron Laboratory (Michigan State)
NSF National Science Foundation.
NSF National Sanitation Foundation. ENVIRO
NSFNET The national backbone network, funded by the National Science Foundation and operated by the Merit
Corporation, used to interconnect regional networks such as WESTNET to one another.
NSLS National Synchrotron Light Source (BNL).
NSNS National Spallation Neutron Source (ORNL).
NSPS New Source Performance Standards. (from CAA and CWA)
NSR Neveu-Schwarz-Ramond
NSRC National Synchrotron Research Centre. (Thailand)
NSRRC National Synchrotron Radiation Research Center (Taiwan).
NSS Neutron Spallation Source.
NSS Nuclear Science Symposium.
NSVZ Novikov-Shifman-Vainshtein-Zakharov.
NT Windows NT is a 32-bit operating system that supports preemptive multitasking. There are two
versions of Windows NT: a network server and a workstation.
NTF No Trouble Found.
NTF Neutron Therapy Facility
NTG Neue Technologien GmbH. (German engineering company)
NTIA National Telecommunications Information Administration.
NTIS National Technical Information Service (U.S. Dept. of Commerce, Springfield, VA).
nTOF neutron Time-Of-Flight facility. (CERN)
NTP Need To Proceed
NTP National Toxicology Program. A part of USPHS.
NTP Network Time Protocol
NTS Non-compliance Tracking System.
Nu The Greek letter (n). See TUNE.
Nuclear Instrumentation Methods See NIM.
Nuclear Physics Injector See NPI.
NUFO National Users Facilities Organization.
NuMI NeUtrinos at the Main Injector. An experiment that fires neutrinos from the Main Injector at FermiLab
toward an underground target 730 km (about 430 miles) away in Soudan, Minnesota.
NuPECC Nuclear Physics European Collaboration Committee.
NuPNET Nuclear Physics NETwork.
NuSAG Neutrino Scientific Assessment Group.
NUST National University of Sciences and Technology. (Pakistan)
NuSTAR Nuclear Spectroscopic Telescope ARray.
NUSX Mont Blanc NUSEX underground detector.
NUT Newman-Unti-Tamburino
NuTeV NeUtrinos at the TEVatron experiment (FNAL).
NVBL National Virtual Biotechnology Laboratory (DOE)
NWPA Nuclear Waste Policy Act of 1982.
NZE Near Zero Emittance.
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OA Office of Assurance (SLAC)
OAL Office of Administrative Law. (California)
OAS Office of Assessment and Support.
OASIS Organization for the Advancement of Structured Information Standards.
OBE One Boson Exchange
OBER See DOE OBER.
OBS Organization Breakdown Structure.
OCCG Operations Computing Coordinating Group.
Occupational Safety and Health Administration See OSHA.
OCFO Office of the Chief Financial Officer.
OCIO Office of the Chief Information Officer. (SLAC)
OCL Obligation Control Level.
OCRWM Office of Civilian Radioactive Waste Management.
OD Operations Directorate (SLAC).
Odd Sector Key A PPS key used to open the door of odd-numbered Sectors of the LINAC (except Sector 19).
ODE Ordinary Differential Equations
ODH Oxygen Deficiency Hazards.
ODM Oxygen Deficiency Monitor.
Odor Threshold The lowest concentration at which a substance is able to be smelled by a person with
normal olfactory capability.
OE OErsted.
OE&ED Organization Effectiveness and Employee Development.
OECD Organization for Economic Cooperation and Development.
OECM Office of Engineering and Construction Management (DOE).
OES Governor's Office of Emergency Services. (California)
OFE Office of Fusion Energy.
OFE Oxygen Free Electrolytic (copper).
OFES Office of Fusion Energy Sciences.
Offs The x and y offsets for the center of a magnet in millimeters.
Off-Site Facility A hazardous waste treatment, storage, or disposal area that is located at a place
away from the generating site.
OFI Opportunity For Improvement.
OGC Office of General Counsel. (SLAC)
OGE One Gluon Exchange Model.
OGLE Optical Gravitational Lensing Experiment.
OGSA Open Grid Service Architecture, from the Global Grid Forum.
OHEP Office of High-Energy Physics. (DOE)
OHMTADS Oil and Hazardous Materials Technical Assistance Data System. A computerized data retrieval system
developed by the EPA.
OHP Operational Health Physics. The group charged with the task of monitoring radiation, TLDs, and
preventing radiation accidents.
OIO Office of Independent Oversight.
OIP Operations Improvement Project(s).
OIPRP Office of Intellectual Property and Research Partnerships.
OJT On-the-Job Training.
OLA Operational Level Agreement.
OLC Online Learning Center. (DOE)
OLCF Oak Ridge Leadership Computing Facility (DOE)
OM Open Membranes
OMB Office of Management and Budget.
OMC Occupational Medicine Clinic.
Omega Space In probability theory, the entire field of all possibilities in a given experiment is
represented by the Greek symbol Omega, and is called `Omega Space.' If you are rolling a pair of dice,
for example, the 11 whole numbers from two through twelve are the Omega Space.
OMVPE OrganoMetallic Vapor Phase Epitaxy.
ONC Open Network Computing Group (Sun).
One-Shot An IC used to generate a single output pulse in response to a trigger, as in `one-shot
multivibrator.'
ONR Office of Naval Research (U.S. Dept. of the Navy, Washington DC).
ONS Okamoto-Nolen-Schiffer.
On-Scene Coordinator See OSC.
OO Object-Oriented.
OOA Object-Oriented Analysis.
OOC Ordering Operator Calculus.
OOP Object Oriented Programming.
OOPS Out Of Plane Spectrometer.(MIT-Bates)
OOPSLA Object-Oriented Programming, Systems, Languages and Applications.
OOUI Object Oriented User Interface. OOUIs are object-oriented Graphical User Interfaces (GUIs). In an OOUI,
an object may be a document that knows how to open, print, and shred itself, to be distinguished from a non-object
word processor that knows how to open a document. The OS/2 Workplace '91 shell, with its templates for classes of
interface objects and containers for windows holding other windows, is an OOUI.
OPA Optical Parametric Amplifier.
OPA Office of Project Assessment (SLAC).Office of Planning Assessment (NSF).
OPC Other Project Costs.
OPCPA Optical Parametric Chirped Pulse Amplification
OPE One Pion Exchange
OPEN LOOK A GUI based on X Windows and developed by AT&T. Alternative to Motif.
Open Software Foundation See OSF.
Open Systems Interconnection See OSI.
OpenEI.org Open Energy Information. (DOE)
OpenGATE A collaboration to improve, validate, document and test GATE software.
OPEP One Pion Exchange Potential
OPERA Oscillation Project with Emulsion-tRacking Apparatus.
Operational Health Physics See OHP.
Operations Schedule Long-term schedule of experiments on the accelerator. It is available from The Technical
Director's office in the Technical Division. Previously called Experiment Schedule. Also called the Running Schedule,
or, the Schedule.
Operator A member of the SLAC Accelerator Operations Department who operates the accelerator and beam
transport systems in order to deliver a beam to a team of experimenters. This function involves tuning to
specifications, failure analysis, and PPS procedures.
OPEX OPerational EXcellence (SLAC)
OPI Organization of Principal Interest.
OPIM Other Potentially Infectious Materials.
OPM Office of Personnel Management.
OPOC Organizational Point Of Contact.
OPR OPeRating.
OPR Owner Project Requirement
OPS OPerationS. See Operator.
OR Oak Ridge. See also ORNL.
Oracle A relational database management system which runs on most mainframe computers and networked microcomputers.
Oracle users can use databases on other platforms as if on their own. SLAC has several site licenses for Oracle.
ORAU Oak Ridge Associated Universities
Orbit The path of a beam along a transport line. Originated from storage ring terminology.
ORCID Open Researcher and Contributor ID.
Organic Chemicals A large group of chemicals in which carbon atoms are key constituents. Other key elements
may include sulfur, hydrogen, oxygen, and nitrogen.
ORION A facility for advanced accelerator research based on the Next Linear Collider Test Accelerator (NLCTA)
that is being built at SLAC.
ORM Other Regulated Material (from 49 CFR).
ORNL Oak Ridge National Laboratory (TN)
ORO Oak Ridge Operations Office (DOE).
ORPS Occurrence Reporting and Processing System. (DOE)
ORR Operational Readiness Review
OSA Optical Society of America.
OSC On-Scene Coordinator. The predesignated EPA, Coast Guard, or Department of Defense official who coordinates
and directs Superfund removal actions or Clean Water Act oil- or hazardous-spill corrective actions.
OSC Operating Safety Committee (SLAC)
OSF Operations Support Facility (ALMA telescope - Chile).
OSF An acronym for Open Software Foundation, a consortium consisting of DEC, IBM, HP/Apollo, and other major
vendors of Unix hardware. The group was formed in response to the formation of the Unix International compact.
Now part of The Open Group.
OSFT Open String Field Theory.
OSG Open Science Grid.
OSHA Occupational Safety and Health Administration. The U.S. Government agency in charge of safety in the
workplace. The California State equivalent is CAL/OSHA.
OSI Open Systems Interconnection. The international standard program to facilitate data communication among
computers from different manufacturers. The standard defines seven layers of protocols (Physical layer, Link layer,
Network layer, Transport layer, Session layer, Presentation layer and Application layer). Most of the functionality
in the OSI model exists in all communication systems, although two or three OSI layers may be incorporated into one.
OSP Operational Safety Procedure (or Policy).
OSP Office of Strategic Planning. (SLAC)
OSR Operational Safety Requirement.
OSR Office of Sponsored Research. (Stanford)
OSR Open Science Repository.
OSTP Office of Science and Technology Policy.
OSU Off-Site Use.
OSWER Office of Solid Waste and Emergency Response. A subdivision of EPA.
OTA Office of Technology Assessment. (Federal)
OTIC Orient Tantalum Industry Corporation. (Ningxia, China)
OTL Office of Technology Licensing. (Stanford)
OTQM Odd Truncated Quadrupole-Phonon Model
OTR Optical Transition Radiation.
OTT Office of Technology Transitions (DOE).
OU Organizational Unit. (SLAC)
OUO Official Use Only. Designation of unclassified information that may be exempt from public release
OZI Okubo-Zweig-Iizuka
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P Private (computer drive designation).
P Wastes A federal waste list comprised of substances categorized as acutely hazardous.
P&T Parking and Transportation or Packaging and Transportation.
P(S) synchrotron light monitor.
P2/E2 Plan Pollution Prevention and Energy Efficiency Plan.
P5 Particle Physics Project Prioritization Panel.
PA Preliminary Assessment.
Pa Pascal. A unit of pressure.
PA Project & Activity code. (SLAC)
PAAA Price-Anderson Amendments Act.
PAB Physics & Astrophysics Building (Stanford).
PAC Perturbed Angular Correlation
PAC Particle Accelerator Conference.
PAC Physics / Project Advisory Committee.
PAC Phase and Amplitude Controller.
Packet The unit of data sent across a packet switching network. The term is used loosely defined. While some
Internet literature uses it to refer specifically to data sent across a physical network, other literature
views the Internet as a packet switching network and describes IP datagrams as packets.
Packet Internet Groper See PING.
PACM Potential Asbestos Containing Material.
PACT Projects for the Acceleration and Commercialization (DOE)
PAEC Pakistan's Atomic Energy Commission.
PAESMEM Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring.
PAFD Palo Alto Fire Department.
PAH Polycyclic Aromatic Hydrocarbons.
Pair Production The creation of an electron and a positron from a high energy photon in a strong electric
field such as that surrounding a nucleus. This process is used to create positrons at the positron target.
PAL Pohang Accelerator Laboratory.(Korea)
Paleoparadoxia See Neoparadoxia Repenningi entry
PAMELA Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics.
PAMM Planned Accessible Machine Maintenance or Planned Access for Maintenance and
Modifications. (LCLS)
PANDA Proton ANtiproton annihilation DArmstadt.
PANIC Particles And Nuclei International Conference.
Panic Circuit Part of the linac PPS system that consists of EMERGENCY OFF buttons that will trip off all
the VVSs in the LINAC when depressed.
Panofsky Long Ion Chamber See PLIC.
PAO Proposal Advancement Office.
PAP Performance Assurance Plan (GLAST).
PAP Personnel Access Platform (GLAST).
PAPR Powered Air-Purifying Respirator.
PARC Xerox Corporation's Palo Alto Research Center
PARMELA Phase And Radial Motion in Electron LinAcs. An accelerator simulation program for electron linacs.
(CERN) See also PARMILA.
PARMELLA Phase And Radial Motion in ELectron Linear Accelerators. A modeling and design program for
transport line optics that incorporates beam bunching.
PARMILA Phase And Radial Motion In LinAcs. An accelerator simulation program for linacs. (CERN)
See also PARMELA.
PARS Project Assessment and Reporting System. (DOE)
PARS-II Project assessment and Reporting System.
PASAG Particle Astrophysics Scientific Assessment Group.
PASCOS PArticles, Strings and COSmology (Symposium).
PASHA Package for Automated Snoop Hardware Analysis.
Pattern Receiver Interrupt Multiplexer See PRIM.
PAW Physics Analysis Workstation. A computer program available from CERN, PAW is an interactive utility
for visualizing experimental data in a computer graphical display.
PAWS Parallel Assessment Window System.
PAX Polarized Antiproton eXperiment.
PB Performance Baseline
PB Pep Beamline. (SSRL)
PBGS Partial Breaking of Global Supersymmetry
PBH Primordial Black Holes
PBRT Proton Beam Radio-Therapy.
PBWA Plasma Beat Wave (laser) Acceleration
PBX Private Branch eXchange. A private telephone network used within an enterprise. PBX users share a
certain number of outside lines for making telephone calls external to the private network.
pc Parsec. An astronomical unit of measurement equivalent to 3.26 light years' distance, calculated
using the PARallax of 1 arc SECond .
PC Personal Computer.
PC Protection Collimator.
PCAC Partially Conserved Axial vector Current
PCAST President's Council of Advisers on Science and Technology.
PCB PolyChlorinated Biphenyl. A group of toxic, persistent chemicals used in transformers and capacitors
for insulating purposes and in gas pipeline systems as a lubricant. Further sale or new use was banned by
law in 1979.
PCB Printed Circuit Board.
PCD Power Conversion Department. Engineers, maintains and installs cables for modulators, subboosters
and all power supplies from the injector through the Research Area.
PCDS Photon Controls and Data Systems.
PCE PerChloroEthylene. (aka tetrachloroethylene, or `perc'.)
PCI Peripheral Component Interconnect
PCI Phase Contrast Imaging.
PCM Programmable Control Module.
PCMCIA Personal Computer Memory Card International Association. This group of manufacturers created the
new PCMCIA industry standard adapter. It looks like a credit card and is mounted by pushing it into an
external computer slot, similar to an ATM.
PCMS Project Controls Management System. (FGST)
PCON Phase CONfiguration. The phase of a klystron taken from a model or a saved configuration.
PCR Polymerase Chain Reaction.
PCR Project Closure Review
PCT Parity Charge conjugation and Time reversal.
PCW Process Cooling Water.
PD Project Director.
PDB Protein Data Bank.
PDE Partial Differential Equations.
PDES Phase DESired for a klystron.
PDF Parton Distribution Function or Pair-Distribution Function.
PDF Portable Document Format.
PDF Powder Diffraction File.
PDG Particle Data Group. The PDG is an international collaboration with
affiliations at LBNL, CERN, KEK, INFN, IHEP, SLAC and elsewhere. The PDG reviews the field of particle physics
and compiles and analyzes data on particle properties.
PDM Project or Product Data Management.
PDR Preliminary Design Review.
PDS Pole Divergent Subtraction
PDS Power Density Spectrum.
PE Plant Engineering. A SLAC organizational group merged under Facilities and renamed the Site Engineering
and Maintenance Office (SEM).
PE/BI Plans Examiner/Building Inspector.
PEA Personnel Exclusion Area.
PEC PhotoElectroChemical.
PED Project Engineering and Design.
PED Plant Engineering Department.
PEEM PhotoElEctron Microscopy.
PEG Polarized Electron Gun. A CID injector gun used to generate a polarized electron beam.
PEL Permissible Exposure Limit. Maximum exposure levels for workplace chemicals as determined by OSHA.
PEL Physical ELectronics. Renamed Surface and Materials Science in 2005.
PEMP Performance Evaluation and Measurement Plan. (DOE)
Pencil Beam A beam with low energy spread and low emittance: usually tightly collimated by one or more
adjustable collimators.
Penetration The flow of a hazardous chemical through zippers, stitched seams, pinholes, or other imperfections
in protective clothing material.
penguin A type of Feynman diagram describing the weak decay of a quark through an intermediate quark - weak boson
loop, in which a gluon (or Z or photon) couples to the quarks in the loop, and then decays to a quark - anti-quark pair.
PENULT PENULTimate.
PEO Plant Engineering Operations. (SLAC)
PEP Project Execution Plan.
PEP-N Upgrade to PEP-II (proposed).
PEP-X Synchrotron storage ring project at SLAC utilizing PEP-II. (Proposed)
PER PERsonnel Department.
PERDPM PERioDic Permanent Magnet.
Periodic Permanent Magnet Klystron An advanced generation klystron developed at SLAC, and planned to provide
microwave power for the NLC.
Perl Practical Extraction and Report Language. An interpretive programming language developed by Larry Wall.
Because of its strong text-processing abilities, Perl has become one of the most popular languages for writing
CGI scripts.
Permeation An invisible process by which a hazardous chemical moves through a protective
clothing material.
Permissible Exposure Limit See PEL.
Permissive A pattern gate used to allow the gun to pulse when a set of interlocks is complete. The BCS and
some MPS systems remove the permissive in response to interlock trips. Operators also have control of the permissive.
This is a `fail-safe' method of killing the beam, in that the gun can only pulse when the permissive gate is present.
Permit An authorization, license, or equivalent control document issued by EPA or an approved state agency to implement
the requirements of an environmental regulation, e.g., a permit to operate a wastewater treatment plant or to operate
a facility that may generate harmful emissions.
Persistence The property of a chemical whereby it tends to remain in the environment in its original
molecular form.
Personnel Protection System See PPS.
PERT Program/project Evaluation and Review Technique.
PERT Procurement Evaluation Review Team
PET Positron Emission Tomography.
PETE Photon-Enhanced Thermionic Emission.
PETRA See DESY PETRA
PETS Power Extraction and Transfer Structure. (CLIC)
PEVATRON Accelerator of cosmic rays with energies of several PeV.
PF Photon Factory
PF Protection Factor. That number which when multiplied by the TLV of a substance yields the maximum permissible
concentration in which the respirator in question may be used. Protection factors are assigned to classes of respirators.
PFA Particle Flow Algorithms.
PFIAB President's Foreign Intelligence Advisory Board.
PFMON ProFile MONitor.
PFN Pulse Forming Network.
PG&E Pacific Gas and Electric Company
PGB Pseudo-Goldstone Boson
PGM Plane Grating Monochromator.
P-Gun or PGUN Polarized gun. See also PLS.
pH A measure of corrosivity on a scale from O to 14, with 7 being neutral, acidity increasing toward O and
alkalinity increasing toward 14.
Phase Acceptance See Acceptance.
Phase Advance The phase change of a betatron oscillation over a certain distance(s) which can be a
lattice cell.
Phase and Amplitude Detector See PAD.
Phase and Amplitude Detector Offset See PADO.
Phase and Radial Motion in ELectron Linear Accelerators See PARMELLA.
Phase Configuration See PCON.
Phase Raw See PRAW.
Phase Shift Keying See PSK.
Phase Space A plot of the beam position versus its phase angle.
Phasing To adjust the timing of any periodic device less than 360 degrees.
Phasing To change the timing of a klystron's RF output with respect to the bunch. This will add or subtract energy
from the bunch by causing the bunch to see a greater or smaller accelerating voltage.
PHENIX the Pioneering High Energy Nuclear Interaction eXperiment located at BNL to investigate high energy collisions
between heavy ions and protons.
PHENIX A comprehensive software package for macromolecular structure determination using crystallographic or electron
cryo-microscopy data IB-1770
Phishing The practice of sending false email in an effort to trick the receiver into revealing information
that can be used to perpetrate identity theft. Phishers direct the unwary to sites that look legitimate, but are not.
PHM Klystron summary display indicating that the station mean phase is out of tolerance.
PHM PHase Mean.
PHMC Polynomial Hybrid Monte Carlo
PHOBOS A detector at RHIC.
phonon wave-like vibration of an atom in a solid.
Photomultiplier A photon to current transducer amplifier which uses the photoelectric effect and secondary
emissions in cascaded diode cells to produce a measurable electric current from a relatively weak light source.
Photon A particle of light. In 1889, Max Planck postulated that light is not continuous, but comes in bunches,
or quanta. Each of these granular quanta of light is made up of photon particles.
photonics The technology of using particles of light as carriers of information.
PHP Personal Home Page (original meaning). General purpose scripting language developed by Rasmus Lerdorf.
PHTN Photon.
Physical Address A grouping of numbers that identifies a particular piece of computer hardware connected
to a local area network or other data communications system. Contrast with logical address.
Physical ELectronics See PEL.
PHYSTAT International Conference on Statistical Problems in Particle Physics, Astrophysics and
Cosmology.
PIC Particle-In-Cell
PIC Port d'Informació Cientifica. (Scientific Information Harbour)
PIC Product of Incomplete Combustion.
PIC Person In Charge. The person in charge of laboratory response to emergencies.
PIC Pocket Ion Chamber.
PIC Protection Ion Chamber.
Picobarn A unit of area equal to 10 to the minus 12 barns. Used to measure cross-sections in
nuclear and particle physics.
Picocurie Measurement of radioactivity. A picocurie is one million millionth, or a trillionth, of a
curie, and represents about 2.2 radioactive particle disintegrations per minute.
Picocuries Per Liter A unit of measure used for expressing levels of radon gas. See also Picocurie.
PICSEL Physics with Integrated Cmos Sensors and ELectron machines.
Picture Element See Pixel.
PID Photo-Ionization Detector.
PID Particle IDentification.
PIE Precourt Institute for Energy. (Stanford)
PIE Process Improvement and Efficiency.
PIER Promoting Inclusive and Equitable Research (DOE)
Pig A container, usually lead, used to ship or store radioactive materials.
PII Personally Identifiable Information.
PILATUS PIxel ApparaTUs for the Sls project.
Pile The fuel element in a nuclear reactor.
PIM Profile Intensity Monitor.
PIMC Path Integral Monte Carlo
PIMMS Proton and Ion Medical Machine Study.
PING Packet INternet Groper. A program which is useful for testing and debugging networks. It sends an ICMP
Echo packet to the specified host, and waits for a response. It reports successor failure and statistics about
its operation. The term is used as a verb: Ping host X to see if it is up!
PingER Ping End-to-end Reporting.
PIP Project Implementation Plan. (ILC)
Piracy Unauthorized copying of software.
PIS Primary Instrument Scientist.
PISL Pi-mode stabilizing loops
PITZ PhotoInjector Test Facility, Zeuthen. (DESY)
PIV Personal Identification Verification.
Pixel Picture element. A dot of video graphics that can be in either an on or off state. The number of pixels
determines the resolution. Resolution is the number of pixels on the monitor and is determined by multiplying the
number of horizontal pixels by the number of vertical pixels. For example, VGA is 640 x 480 or 307,200 pixels
on the monitor.
PJB Pre-Job Briefing
PJLZ Parrinello-Jona-Lasinio-Zwanziger.
PKU3 Peking University 3rd. A 1.3 gigahertz TESLA-type nine-cell niobium superconducting cavity.
PL Pulsed Linac (FEL).
PL/1 Programming Language 1. General-purpose language used for both scientific and business applications.
Plant Engineering See PE.
PLAS Plastic detector.
PLC Programmable Logic Controller.
PLD Pulsed Laser Deposition.
PLEDGE PoLicy Enforcement in Data Grid Environments. (NARA)
PLI Project Leadership Institute. (DOE)
PLIC Panofsky Long Ion Chamber. A gas filled cable running along the linac housing or primary beam transport
line used to detect a mis-steered beam. The point where the beam is lost can be determined from the time of
arrival of the ion shower that the lost beam sprays into the cable-chamber. Conceived by Wolfgang K. H. Panofsky,
SLAC Director Emeritus.
PLS Pohang Light Source. (Korea)
Plug Compatibility Manufactured hardware that is designed to be interchangeable with another vendor's
product, even though internal details may differ.
PLUME Pixelated Ladder with Ultra-Low Material Embedding. (ILC)
PLUT DESY PLUTO detector.
PM Peripheral Monitors.
PM Project Management.
PM Preventive Maintenance.
PM Pulsed Magnet.
PM Performance Measures.
PM Protection colliMator.
PM Pulse-bending Magnet.
PMAG Project Management Assurance Group.
PMAAG Project Management Advisory and Assurance Group
PMB Performance Measurement Baseline.
PMC PCI Mezzanine Card. (GLAST)
PMCS Project Management Control System
PMD Photon Multiplicity Detector.
PME Plant Maintenance Electrical.
PMI Plant Maintenance Instrumentation.
PMM Plant Maintenance Mechanics.
PMN Pre-Manufacture Notification.
PMO Project Management Office. (SLAC)
PMPS Photon Machine Protection System
PMS Program Management System.
PMS Peripheral Monitoring Stations.
PMS Plant Maintenance Services.
PMT PhotoMultiplier Tube. See also Photomultiplier.
PMU Plant Maintenance and Utilities Building.
PMV Pulse-bending Magnet Vertical.
PNC Parity NonConservation, or Parity NonConserving.
PNGB Pseudo-Nambu-Goldstone Boson.
PNL An abbreviation for `Panel.'
PNNL Pacific Northwest National Laboratory.
PNT Position, Navigation and Time.
PO Purchase Order.
PO Pump Out.
POAM Plan Of Action and Milestones.
POC Point Of Contact or Point of Connection.
Pockels Cell A crystal which changes its angle of light polarization when submitted to a high voltage.
A Pockels cell is used in the PLS to chop the laser beam and also for polarization and intensity control.
It is useful for fast switching and control of polarized light beams.
POD Print-On-Demand.
POHC Principal Organic Hazardous Constituent.
POI Person Of Interest.
Poisson A modeling program used for calculating magnetic fields.
Poisson A type of statistical distribution (see also Gaussian) named after the mathematician Simeon
Denis Poisson.
Polling Connecting to another system to check for things like mail or news.
Polychlorinated Biphenyl See PCB.
POMDP Partially Observable Markov Decision Process.
Pomeron A color-neutral collective partonic excitation the aggregate mechanism responsible for elastic scattering.
POMM Planned Operational Machine Maintenance. (LCLS)
POP Post Office Protocol. A protocol used to retrieve e-mail from a mail server. Most e-mail applications
(sometimes called an e-mail client) use the POP protocol, although some can use the newer IMAP (Internet
Message Access Protocol).
POPBCI POst Processor for Beam Coupling Interfaces.
PosiPol Polarized positrons.
Positron A particle with a mass equal to an electron but with opposite charge. First postulated by
P.A.M. Dirac in 1929, and experimentally discovered by C.D. Anderson in 1931.
POSS Palomar Observatory Sky Survey (1950-1955).
Post Telephone and Telegraph Administration See PTT.
Postmaster The person responsible for taking care of mail problems, answering queries about users, and
other related work at a site.
PostScript A commonly-used graphics description language designed for use with computer printers. Most
modern computer word processors and graphics programs can produce PostScript output.
POTW Publicly-Owned Treatment Works.
POTW Plan Of The Week.
POW Plan Of the Week. (SLAC)
Power Conversion Department See PCD.
Power Supply Controller See PSC.
Power Supply Operations Group See AME.
Power Teks. See AME.
PPA Particle Physics and Astrophysics (Directorate-SLAC). Changed in August 2007. Was Particle and
Particle Astrophysics (Directorate-SLAC).
PPARC Particle Physics and Astronomy Research Council (UK).
ppb Parts per billion.
PPB Planning and Policy Board. (Stanford University)
PPC Parallel Plate Chamber
PPDG Particle Physics Data Grid. Collaboration formed in 1999 to develop a worldwide distributed
computing model. COMPUTING
PPE Personal Protective Equipment.
PPL Pervasive Parallelism Laboratory. (Stanford - Computing)
PPL Pole PLate.
PPM Piecewise Parabolic Method.
PPM Periodic Permanent Magnet.
ppm Parts per million.
PPM Focusing Periodic permanent magnet focusing. Uses an array of closely spaced magnetic lenses of
alternating polarity, driven by ring- shaped, high-energy, rare earth magnets (which provides table
fields and require no input current).
PPN Parametrized PostNewtonian
PPO Program Planning Office, an ES&H Division Department
PPP Point to Point Protocol. A protocol that allows a computer to use the TCP/IP protocols and become a
full Internet member with a standard phone line and a hi-speed modem. Replaces SLIP.
PPP Preferred Procurement Products. (DOE)
PPPA Poison Prevention Packaging Act. (Federal)
PPPL Princeton Plasma Physics Laboratory.
PPRC Polarized Photocathode Research Collaboration.
PPS Pulses Per Second.
PPS Personnel Protection System. A safety system designed to protect people from radiation hazards. It
includes the access control system of radiation areas and the radiation detection systems (BSOIC and BCS).
PPSN Public Packet Switched Network, e.g., Telnet, Tymnet, Uninet in the U.S., Datapac in Canada,
Datexp in Germany.
PQCD Perturbative QCD
PQFT Perturbative Quantum Field Theory.
PR beam position monitor, cherenkov cell, phosphor screen.
PRA Paperwork Reduction Act. (1995)
PRBs Permeable Reactive Barriers.
PRC People's Republic of China.
PRC PRoperty Control.
PRCS Permit Required Confined Spaces.
PRD Physics Requirements Document.
PRD Pressure Relief Damper.
PREC Physical Requirements and Exposures Checklist.
Pre-kicker A small pulsed magnet used on SLC to cancel the kick received by the second bunch on the previous
turn of the NDR.
Preprint A manuscript intended for publication but circulated among peers for comment prior to being
submitted for publication.
Preset Buttons PPS search devices which need to be activated by an operator when searching an accelerator area.
These buttons are placed strategically in the beam housing to ensure that the search team does a complete job of
searching all the nooks and crannies in the tunnel.
Primary Waste Treatment The first steps in wastewater treatment. Screens and sedimentation tanks are used to
remove most materials that float or will settle. Primary treatment results in the removal of about30 percent
of carbonaceous biochemical oxygen demand from domestic sewage.
PRIME Post-RefInement and MErging. Software program for analyzing data from X-ray laser experiments.
Princeton-Stanford Storage Rings See Stanford-Princeton Storage Rings.
Print Server A network server assigned to manage local or remote printers and printer queues. The print server
keeps track of print jobs, allows manipulation of print queues, and sends print jobs to various printers.
Priority Pollutants A list of chemicals selected from the list of toxic pollutants by the EPA as priority
toxic pollutants for regulation under the Clean Water Act.
PRISM Phase-Rotated Intense Slow Muon Source (Osaka).
Private Branch Extension See PBX.
PRL Physics Review Letters. PHYSICS
PRL Phase Reference Line (For PAD).
PRL Positron Return Line.
Probability A number between zero and one that represents the chance of occurrence of a given event,
wherein a probability of zero means there is no chance of the event occurring, and a probability of one
means the event must happen. (A fifty percent chance of occurrence is a probability of one half).
Process Any autonomous program executed by a computer's CPU is a process. Sometimes called a job.
Profile Monitor A screen inserted in a beam transport line to view the beam cross section. The visible
emission created by the beam exiting the screen's phosphor coating (usually zinc sulfide) is viewed by a
video camera and the picture transmitted to the Control Room. Profile monitor screens can usually be
inserted and removed remotely by the machine operators.
Program Deputy The physicist temporarily in charge of the current program. Program deputies usually have
the `duty' for a period of one or two weeks.
Programmable Input/Output Processor See PIOP.
Programmable Synchronization Unit See PSU.
Programmable Width Unit See PWU.
Programmed Data Processor See PDP-11.
Programming Language 1 See PL/1.
Prop. 65 Safe Drinking Water and Toxic Enforcement Act of 1986, citizen's referendum in California.
PROSCAN Proton therapy project at the Paul Scherrer Institute (PSI).
Protection Factor See PF.
Protection System See PTS.
Protocol A formal description of message formats and the rules two computers must follow to exchange
those messages. A Protocol can describe low-level details of machine-to-machine interfaces(e.g., the order
in which bits and bytes are sent across a wire) or high-level exchanges between allocation programs (e.g.,
the way in which two programs transfer a file across the Internet).
Proxy The mechanism whereby one system fronts for another system in responding to protocol requests.
Proxy systems are used in network management to avoid having to implement full protocol stacks in simple
devices, such as modems.
PRP Potentially Responsible Party.
PRP Proposal or Program Review Panel.
PRST-AB Physical Review Special Topics - Accelerators and Beams.
PRT Participating Research Team (SSRL)
PRV Pressure Relief Valve
PS Pico-Second.
ps A commonly used abbreviation for PostScript. Often used as the extension portion of a computer file
specification containing PostScript language commands, as in myletter.ps.
PS Program Support. (DOE)
PS Power Supply.
PS vacuum Pumping (above housing)
PS Pressure Switch.
PS2 high-energy Photon Science.
PSA PCB waste Storage Area. SLAC
PSAD Preliminary Safety Analysis Document.
PSB Power Supply Board.
PSC Planar Spark Counter.
PSD Prevention of Significant Deterioration. (from CAA)
PSD Pulse Shape Discrimination.
PSE Power Systems Engineering group (SLAC).
PSES Pretreatment Standards for Existing Sources. (from CWA)
PSF Point Spread Function.
PSF Planetary Systems and Star Formation.
Psi The Greek letter `y.' See also Phase Advance.
PSI Paul Scherrer Institute.(Switzerland)
PSI A revolutionary long-lived meson discovered simultaneously at SLAC and MIT in 1974. Burton Richter
(SLAC) and Sam Ting (MIT) shared the 1976 Nobel Prize in Physics for the discovery of this particle,
called J by the MIT team.
PSI Pounds per Square Inch (unit of pressure).
PSI Protein Structure Initiative (NIH/NIGMS).
PS-II PhotoSystem-II
PSK Phase Shift Keying. Used in the SLED system to add the energy stored in the sled cavity to that being
produced by the klystron. The PSK knob moves the envelope of the RF for sector 2-30with respect to the beam.
It affects both beams, unlike the phase ramp knob which is used to adjust the e+ and e- beam energies separately.
PSLB Photon Science Laboratory Building. (Bldg. 057) Renamed Arillaga Science Center in 2017.
PSM vacuum Pumping (Mech.) (above housing)
PSN Proper Shipping Name. (from 49 CFR)
PSNM Power Supply NaMe or serial number.
PSNS Pretreatment Standards for New Sources. (from CWA)
PSPS Public Safety Power Shutoff (PG&E)
PSUSY ParaSUperSYmmetry.
pT Transverse momentum.
PTA Projects-Tasks-Awards. (Stanford)
PTE Potential To Emit.
PTEC Physics Teacher Education Coalition.
PTFE PolyTetraFluorEthylene CHEMISTRY MATERIALS
PTPS Pulse To Pulse Stabilizer.
PTS ProTection System. The SLAC operational group charged with designing and troubleshooting electronics systems
used in Beam Containment and PPS.
Public Packet Switched Network See PPSN.
PUE Power Usage Effectiveness.
PULSE Photon Ultrafast Laser Science and Engineering center (SLAC).
Pulsed Amplitude Unit See PAU.
Pulsed Bend Horizontal See PBH.
Pulsed Power Output Module See PPOM.
Pump down Depressurize.
Pump Probe A technique developed for the observation of ultrafast events. A sample of material is 'pumped' at
regular intervals to create discrete events, and as the sample is changing, the experimenters 'probe' the response
of the system to the created excitation events.
PUR Purchasing.
PVA PolyVinyl Alcohol.
PVA Process Variable Access (Computing)
PVC PolyVinylChloride.
PVM Parallel Virtual Machine. A message-passing library and processor daemon for coordinating tasks across
processors. Public domain from Oak Ridge National Lab. Like Express and Linda, usage has been growing explosively.
Used in conjunction with batch programs like Condor on MPPs or clusters to take better advantage of multiple processors.
PVM node programs aren't currently under Condor control.
PVSS ProzeflVisualisierungs und SteuerungsSystem, an LHC control software.
PWA Partial-Wave Analysis.
PWC Proportional Wire Chamber
PWFA Plasma-based WakeField Acceleration.
PWHA Pre-Work Hazard Assessment.
PWR Pressurized Water Reactor.
PWSA Ports and Waterways Safety Act. (Federal)
PWT Plane Wave Transformer.
PXE Preboot eXecution Environment
Pyroehoric Capable of igniting spontaneously when exposed to dry or moist air at or below 130 degrees
F (54.44 C).
Pyrolysis The destruction of molecular composition through heating, resulting in smaller, simpler, and
generally less toxic compounds.
Back to top
Q A general reference to the strength of a quad where: q = 1/Focal length.
Q The physical symbol for electric charge, usually measured in coulombs.
QA Quality Assurance.
QA Accelerator Quadrupole.
QA&C Quality Assurance and Compliance.
QA/R Quality Assurance/Reliability.
QAP Quality Assurance Program.
QATS Quality Assurance Tracking System
QC Quality Control.
QCD Quantum Chromo-Dynamics.
QCDOC QCD-On-a-Chip, a new class of parallel computers.
QCDSP Quantum Chromodynamics on Digital Signal Processors
QCDSR Quantum Chromo-Dynamics SumRules
QD Quadrupole Defocusing.
QDI QuaDrupole Insertion.
QDM QuaDrupole Matching.
QED Quantum Electro-Dynamics.
QF Quadrupole Focusing.
Q-FARM Quantum Fundamentals, ARchitectures, and Machines
QFP Quasi-infrared Fixed Point
QFT Quantum Field Theory
QFTH Quantum Field THeory
QG Quantum Gravity.
QGP Quark - Gluon Plasma
QGR Quantum General Relativity
QH Quantum Hall
QHD Quantum HadroDynamics
QIP Quality Implementing Procedures.
QIPs Quality Implementing Procedures.
QIS Quantum Information Science
QISM Quantum Inverse Scattering Method.
QKT Quaternionic Kahler with Torsion
QKZ Quantized Knizhnik-Zamolodochikov
QLO Qualified Laser Operator.
QM Quantum Mechanics
QMC Quark Meson Coupling
QMD Quantum Molecular Dynamics.
QME Quantum Master Equation
QND Quantum NonDemolition
Q-NEXT NEXT generation Quantum science and engineering. A national quantum information science research center (DOE)
QNGT Quantum Nonsymmetric Gravitation Theory
QPA Quantum Privacy Amplification
QPM Quark Parton Model
QPOS QuasiPeriodic OScillations.
QRCM Quantitative Reliability Centered Maintenance.
qRIXS (high-resolution) momentum resolved RIXS
QRPA Quasiparticle Random Phase Approximation
QSO Quasi Stellar Objects (Quasars)
QTRM Quadrupole TRiM. An extra winding on a quadrupole magnet used for making small adjustments to the field.
Sometimes wired to add a small dipole field to the quadrupole, usually for steering purposes.
Quad See Quadrupole.
QUaD QUest at Dasi. Project utilizing the Q U Extra-galactic Survey Telescope (QUEST) instrument at the South
Pole that was installed on the mechanical structure from a previous experiment called DASI
(Degree Angular Scale Interferometer).
Quadrupole A four pole magnet used to focus beams. The strength of the field is proportional to the
distance from the center. The focusing is in one plane only. In the other plane, the field is defocusing.
Quadrupoles may be wired to be horizontally focusing (vertically defocusing) or horizontally defocusing
(vertically focusing). At SLAC, they are named after their horizontal effect on the beam.
Quadrupole TRiM See QTRM.
Quaero A web-based computer tool which allows physicists worldwide to search data from Fermilab's DZero
experiment. Developed by physicist Bruce Knuteson. Quaero is Latin for 'I search.'
( http://quaero.fnal.gov )
Qubit One QUantum BIT of information.
Quench A change of phase in a superconducting magnet in which the superconducting properties are lost. The energy
released can destroy the magnet, if proper precautions are not taken to safely dissipate the stored energy.
Quencher A Superconducting Triplet protection subsystem to initiate a quench and turn off the final
triplet. This is done using a capacitive discharge to warm up the wire and bring it out of superconductivity.
QUEST Q U Extra-galactic Survey Telescope. (South Pole)
QUEST QUasar Equatorial Survey Team.
Quick Access An access to a PPS-controlled area defined as being for less than two hours and with
fewer than five people.
QWT Quarter Wave Transformer.
Back to top
R Region.
R Roentgen.
R&D Research and Development.
R2A2 Roles, Responsibilities, Authorities and Accountability (ES&H).
R2As Roles, Responsibilities and Authorities.
RA Radiation Area.
RA Return Air.
RACT Reasonably Available Control Technology (from CAA).
RAD Radiation Absorbed Dose. A unit of absorbed dose of radiation. One RAD of absorbed dose is equal
to .01 joules per kilogram.
Radiation Absorbed Dose See RAD.
Radiation Physics See RP.
Radiological Worker Worker whose job assignment requires work on, with, or in the proximity of
radiation-producing machines or radioactive materials. A radiological worker has the potential of being
exposed to more than 0.1 rem (1 mSv) per year, which is the sum of the dose equivalent from external
irradiation and the committed effective dose equivalent from internal irradiation. A "radiological worker"
may also be referred to as a "radiation worker" or a "rad worker."
Radionuclides Atoms which give off various radiations through spontaneous nuclear events.
RAFEL Regenerative Amplifier Free-Electron Laser
RAID Redundant Array of Independent/Inexpensive Disks.
RAIRS Reflection Absorption Infrared Spectroscopy
RAL Rutherford Appleton Laboratory (UK).
RAM Random Access Memory.
RAM RadioActive Material.
RAMSY RadioActive Materials Storage Yard.
Random Variable In probability theory, the event whose probability of occurrence is in question is
the `random variable.'
RAP Remedial Action Plan.
RARP Reverse Address Resolution Protocol. The Internet protocol a diskless host uses to find its Internet
address at startup. RARP maps a physical (hardware) address to an Internet address.
RAS Russian Academy of Science.
RAS Reliability, Availability, and Serviceability. Part of ATCA specifications.
RASICAM Radiometric All-Sky Infrared CAMera. (SLAC)
RASK Restricted Access Safety Key. Used to enable magnets to be tested while personnel are present in an area
where the power supplies are normally interlocked off with the PPS system. The RASK key circumvents the normal
protection interlock system, and must be used under a strict set of operational procedures that are designed to
prevent accidents during the magnet test.
Rate LIMit See RLIM.
RCA Radiologically Controlled Area.
RCE Reconfigurable Cluster Element. (ATLAS)
RCF RHIC Computing Facility, located at BNL.
RCFT Rational Conformal Field Theory
RCM Radiological Control Manager
RCMBNR ReCoMBiNeR.
RCNP Research Center for Nuclear Physics
RCRA Resource Conservation and Recovery Act. (42 U.S.C. Ch. 82, Sec. 6901 et seq)
RDBMS Relational DataBase Management System.
RDC Remote Desktop Connection.
RDDS Rounded Damped Detuned Structures. (NLC)
RDDS Rounded Damped-Detuned Structure
RDF Radical Distribution Function
RDP Remote Desktop Protocol.
RDR Reference Design Report (ILC).
RDTS Rausch De Traubenberg and Slupinsky
REA Registered Environmental Assessor. (CH&SC Sec. 25570 et seq)
REC REConstruction of the physical properties of events (data). (HEP)
Recharge Zone A land area where rainwater, or infiltration from surface streams or impoundment areas or other
sources soaks into the ground and enters an aquifer.
REDE Resonance depolarization.
Reduced Instruction Set Computer See RISC.
REE Rare Earth Elements.
Reflected Power An RF engineering parameter that indicates the quality of impedance matching between any two power
devices in an RF system. The lower the reflected power, the better the impedance match at any given frequency.
Refractory Organics Organic compounds which are resistant to decomposition through burning or high temperature treatment.
Refrigerated Baffle See DPS.
REG Research Electronics Group.
REG Research Engineering Group.
Regional Response Team See RRT.
REL Recommended Exposure Level. (from NIOSH)
Relativistic A mechanical or electrical system that involves velocities close enough to the speed of light to
require the formulas of relativistic mechanics is said to be `relativistic.' If the velocities involved in the
system are far enough sub-light to be approximated by Newtonian mechanics, then the system is said to
be `non-relativistic.'
REM Readiness and Emergency Management Team (ES&H).
REM Roentgen Equivalent Man. A unit of radiation absorbed by a person. A `q' multiplication factor is used to
adjust for different type of radiation (having differing effects on the human body).
REML Radiological Environmental Monitoring Laboratory.
Remote Amplifier Monitor See RAMM.
Remote Procedure Call See RPC.
Remote Procedure-Co-System A subset of a distributed computing environment that includes a programming library,
network-resource mapping, and binding services. These tools provide the means for client processes to execute
procedures on a remote server.
REMP Radiological Environmental Monitoring Plan.
RENO Reactor Experiment for Neutrino Oscillations. (Korea)
REPMM Rare Earth Permanent Magnet Multipoles.
REPMM Rare Earth Permanent Magnet Material.
Reportable Occurrence A DOE administrative definition. Reportable occurrences are defined by DOE order 5000.3A.
and include all emergencies and unusual occurrences. These events are reported by the EOIC in a Notification note
book (a binder on the MCC Console desk).
Reportable Quantity See RQ.
RES RESonant.
Research Yard The area east of the BSY and including End Stations A, B, and C. This term is not generally used
for the SLC collider hall or any facilities east of Beam Dump East.
Restricted Access A PPS beam housing access status designed to allow the safe operation of electrical hazards
in the beam housing without having to prepare for beam operations that require the extra discipline of
radiation safety. This allows the safe testing of magnets and power supplies without meeting all of the requirements
of the BAS that would be required to get to the `no access' state.(Does not exist in CID and LINAC.)
Reverse Bend See RB.
Rexx REstructured eXtended eXecutor (programming language).
RF The microwave radio frequency power used to accelerate particles in the LINAC (2856 MHz) and in the ring
cavities (714 MHz). Generally, any oscillation frequency above 30 KHz (above audio).
RF RadioFrequency.
RFAR Radio Frequency Accelerator Research.
RFARD Radio Frequency Accelerator Research Division. (SLAC)
RFARE RF Accelerator Research and Engineering Division. (SLAC)
RFARED RF Accelerator Research and Engineering Division.
RFC Request for Comments. The document series, begun in 1969, which describes the Internet suite of protocols
and related experiments. Not all RFCs describe Internet standards, but all Internet standards are written as RFCs.
RFI Request For Information.
RFP Request For Proposal
RFQ Request For Quotation
RFQ Radio-Frequency Quadrupole
RFQD Radio-Frequency Quadrupole Decelerator.
RG Renormalization Group
RGA Residual Gas Analyzer
RGB Red, Green, and Blue.
RGD Radiation Generating Devices.
RGE Renormalization Group Equation
RGT Renormalization Group Transformation
RHEED Reflection High-Energy Electron Diffraction.
RHEL4 Red Hat Enterprise Linux 4.
RHIC Relativistic Heavy Ion Collider. A Brookhaven National Lab collider that generates 100 Gev/n per beam.
RHM Running Hour Meter.
RHMC Rational Hybrid Monte Carlo.
RHW Restricted Hazardous Wastes.
RI/FS Remedial Investigation/Feasibility Study.
RIA Rare Isotope Accelerator.
RIA Relativistic Impulse Approximation
RICH Ring-Imaging CHerenkov detector.
RID Review Item Discrepancy.
RID Ratio of Intensity Driver.
Rigidity Factor A database constant used in the calculation of KMOD and equal to 33.356. BDES =
KMOD X Rigidity X Length.
RIKEN Institute of Physical and Chemical Research in Saitama, Japan. Active in many areas of physics, especially
nuclear physics.
Ring Network LAN in which multiple stations are each connected to an adjacent workstation. Communications must be
relayed through the adjacent stations to reach the desired station.
Ring To LINAC See RTL.
RISC Reduced Instruction Set Computer. See also RISC Architecture.
RISC Architecture The objective of this computer technology is to reduce the complexity of instructions so
each can be completed in a CPU clock cycle, producing faster results.
RISE Raising Interest in Science and Engineering. (Stanford-DOE program )
Risk The probability of an adverse health effect as a result of exposure to a hazardous substance or substances.
Risk Assessment The use of available information to evaluate and estimate exposure to a substance(s) and its consequent
adverse health effects.
Risk Management The process of integrating risk-assessment results with engineering data and social, economic, and
political concerns, then weighing alternatives to select the most appropriate public health action (ranging
from public education to interdiction) that will lead to reduction or elimination of the identified risk.
RIST Radioactive Ion Source Test
RIXS Resonant Inelastic X-ray Scattering.
RJ-45 connector Small plastic phone-jack style (but different size) connecter used (at SLAC) on 10base-T
Ethernet connections.
RLA Recirculating Linear Accelerator.
RLIM Rate LIMit. A common effect of the MPS is to rate limit the beam.
RM Records Management.
RM Requirements Management.
RMA Return Merchandise Authorization.
RMA Radiological Materials Area.
R-Matrix A transport matrix which describes the path of a charged particle through a magnet lattice. It may
be used to calculate the position and angle of a particle at point B from a known position and angle at point A.
RMCL Recommended Maximum Contaminant Level.
RMDF Radiation Materials Declaration Form
RMF Response Matrix File.
RMF Risk Management Framework.
RMMA Radioactive Materials Management Area.
RMPP Risk Management and Prevention Program. (CH&SC Sec. 25531 et seq)
RMS Root Mean Square. The RMS value of the calculated-by-history buffer.
RNA RiboNucleic Acid
RNB Radioactive Nuclear Beam
RNL Relativistic Nonlocality
RNO Reduced normal-ordering
RO Reverse Osmosis.
ROB Research Office Building
ROC Read-Out Chip.
ROCKSTAR Robust Overdensity Calculation using K-Space Topologically Adaptive Refinement.
ROD Record Of Decision.
ROD Repair Opportunity Day.
ROD The SSRL Research and Operations Division.
ROG Reactive Organic Gases.
ROI Regions Of Interest.
ROI Return On Investment.
Roller Screen A type of beam monitoring screen that `rolls' in and out of the beam path.
ROM Read Only Memory.
ROMEOs Retired Old Men Eating Out. (Informal SLAC social club).
ROOT An object-oriented data-analysis framework developed at CERN.
ROR Receiver Over Run.
Ross Diagram A timing diagram showing the beam codes and their firing order for a specified machine rate. Named for
Marc Ross, its originator.
Route The path that network traffic takes from its source to its destination.
Router A dedicated computer (or other device) that sends packets from one place to another, paying attention to the
current state of the network.
RP Responsible Party.
RP Radiation Physics. The SLAC organization group responsible for Radiation shielding design, Beam Line containment
and BAS definitions. Also called Radiation Protection.
RP&TC Research Partnerships & Technology Commercialization. (SLAC)
RPA Rapid Prototype Array.
RPA Random Phase Approximation
RPAR See Special Review.
RPC Remote Procedure Call. A type of interprocess communication that allows a process on one computer to call a process
located in another computer.
RPD Radiation Protection Department. (SLAC)
RPFO Radiation Protection Field Operations group. (SLAC)
RPG Radiation Physics Group.
RPM Risk Prioritization Model.
RPO Recovery Point Objective (Business Continuity Plan).
RPP Respiratory Protection Program.
RPP Radiation Protection Program
RPP Review of Particle Physics. A biennial review published by The Particle Data Group which summarizes much of
particle physics. Formerly titled Review of Particle Properties, RPP is available on the web at
http://pdg.lbl.gov
RPTC Rinecker Proton Therapy Center, located in Munich, Germany. Contains Europe's first clinical proton-therapy
system.
RPTC Research Partnerships and Technology Commercialization. (SLAC)
RPWIA Relativistic Plane Wave Impulse Approximation.
RQ Reportable Quantity. (from 49 CFR) The quantity of a hazardous substance that triggers reports under CERCLA.
If a substance is released in amounts exceeding its RQ, the release must be reported to the National Response
Center, the State Emergency Response Commission, and community emergency coordinators for areas likely to be affected.
RQRPA Renormalized Quasiparticle Random Phase Approximation
RR Ramond-Ramond
RRA Roles, Responsibilities, and Authorities (ES&H).
RRAT Rotating RAdio Transients.
RRCAT Raja Ramanna Centre for Advanced Technology. (India)
RRD Round Robin Database tool.
RRQM Reconstruction of Relativistic Quantum Mechanics
RRR Residual Resistance Ratio
RRT Regional Response Team. Representatives of federal, local, and state agencies who may assist in coordination
of activities at the request of the On-Scene Coordinator before and during a Superfund response action.
RS-232 The Electronics Industry Association standard defining interface voltage and current levels and other
signal characteristics for connecting digital equipment to a transmission line.
RSB Research Services/Support Building (Bld. 052).
RSC Radiation Safety Committee.
RSC Rigid Steel Conduit.
RSFP Resonant Spin Flavor Precession
RSO Radiation Safety Officer.
RSOS Restricted Solid On Solid
RSOXS Resonant Soft X-ray Scattering.
RST Russo-Susskind-Thorlacius
RSVP Rare Symmetry Violating Processes. (Brookhaven)
RSWCF Radiation Safety Work Control Form.
RSXS Resonant Soft X-ray Scattering (a type of chamber / end station in LCLS and a type of science
done at LCLS)
RTECS Registry of the Toxic Effects of Chemical Substances. It is published by NIOSH.
RTEMS Real-Time Executive for Multiprocessor Systems.
RTM Rear Transition Modules.
RTML Ring To Main Linac. (ILC)
RTO Recovery Time Objective (Business Continuity Plan).
RTOS Real-Time Operating System.
RTP Rapid-Thermal-Processing.
Rubin Vera C. Rubin Observatory, in Chile, location of LSST experiment
RUF Respirator User's Form
Running Schedule See Operations Schedule.
RVT Restart Validation Team.(SLAC)
RVUE Review of previous data.
RWG Revolutionary Working Group. (SLAC Contract Project)
RWK ReWorK.
RWM Radiation Waste Management group (SLAC)
RWP Radiological Work Permit.
RWQCB Regional Water Quality Control Board.
RWT Radiation Worker Training.
RWTP Rinse Water Treatment Plant.
RXTE Rossi X-ray Timing Explorer satellite
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S A variable for any distance in the direction of the beam or for the length of the bunch itself. Distances
are measured in the `Z' direction.
S Siemens.
S K-XAS An imaging technique using low-energy ranges and the element sulfur.
S&E Safety and Environmental (ES&H). Also, Science and Engineering.
S&H Safety and Health.
S&ORIP Safety and Operational Reliability Improvements Project.
S&R Shipping and Receiving.
S/CI Suspect or Counterfeit Items.
S2C2 Stanford-SLAC Cryo-EM Center
S30XL Sector 30 transfer Line
S3DF SLAC Shared Science Data Facility
SA Supply Air.
SAA Safety Access Area.
SAA South Atlantic Anomaly. Anomaly in earth's magnetic field.
SAA Satellite Accumulation Area.
SAC SLAC Architectural Committee.
SACLA Spring-8 Angstrom Compact free-electron LAser. (RIKEN, Japan)
SAD Safety Analysis / Assessment Document.
SAFARI Spica FAR-infrared Instrument.
Safety Barrel A cylindrical shield used to protect exposed wires like PLIC line junctions. It is made of
metal and always grounded.
Safety, Health, and Assurance A department within the Environment, Safety, and Health (ES&H) Division.
SAG Senior Advisory Group. (US)
SAGE Formerly the Soviet-American Gallium Experiment, now officially named Russian-American Gallium Experiment,
although the original acronym has been retained.
SAGENAP Special Accelerator Group for Experiments in Non-Accelerator Physics
SAGE-S SLAC Accelerating Girls' Engagement in STEM
SAID Scattering Analyses Interactive Dialin
SAL Saskatchewan Accelerator Laboratory.
SALLIE Stanford ALL Image Exchange.
SALT Strategic Arms Limitation Treaty
SALTA Snowmass Area Large-scale Time-coincidence Array.
SAM Software Asset Management
SAM Small Angle Monitor. See also Mini Sam.
SAM Smart Analog Module. A 32-channel module used to digitize analog signals. It is used to monitor the LINAC
waveguide temperatures, small magnet currents, and miscellaneous analog reference signals.
SAM Software Asset Management
SAML Security Assertion Markup Language
SAO Smithsonian Astrophysical Observatory.
SAP Scientific Advisory Panel, initiated by Prop. 65. (CCR Title 22, Sec. 12301 et seq)
SAPE SSRL Accelerator Procedures-Engineering.
SAR Supplied Air Respirator.
SAR Safety Analysis Report.
SARA Superfund (CERCLA) Amendments and Reauthorization Act. Title III of this act created federal community
right-to-know program. See also EPCRA.
SARA Heavy ion facility in Grenoble, France.
SARA-NIKHEF National Center for Computing and Networking Services and the National Institute for Nuclear
Physics and High Energy Physics, based in the Netherlands.
SAREC SLAC Accelerator Research Experimental Committee.
SARS-CoV-2 Severe Acute Respiratory Syndrome CoronaVirus 2
SAS Science Analysis Software. (GLAST)
SASE Self-Amplified Spontaneous Emission.
SASER Acoustic equivalent of a laser.
SASS SLAC Association of Students Seminars.
SAT Site Acceptance Test
SATAN Security Administrator Tool for Analyzing Networks.
SATF Self-Assessment Task Force.
SATIF Shielding aspects of Accelerators, Targets and Irradiation Facilities.
SATS Self-Assessment Tracking System.
SATURNE II Saclay Saturne II proton, charmed meson, and helium nucleus synchrotron.
SAURON Spectroscopic Areal Unit for Research on Optical Nebulae.
SAW Self-Avoiding Walk
SAX Small-Angle Xray.
SAXS Small-Angle X-ray Scattering
SB Senate Bill.
SB Strawman Baseline. (ILC)
SB See SBST.
S-BAND 2856 Mhz. The microwave frequency used to accelerate particles in the LINAC. The wavelength at this frequency
is 10.5 cm, or about 4 and 1/8 inches.
SBBSTR SuBbooSTer. An amplifier station where the RF signal coming from the x6 multiplier is boosted for the
klystrons of a LINAC sector. Subboosters are either klystron tubes or solid state.
SBE State Board of Equalization.
SBI SubBooster Interface. A CAMAC module that handles control and monitoring for each subbooster. It provides
the accelerate and standby triggers to the Subbooster modulators.
SBK Sheet Beam Klystron.
SBNG StarBurst Nucleus Galaxies
SBST SuBbooSTer. An amplifier station where the RF signal coming from the x6 multiplier is boosted for the
klystrons of a LINAC sector. Subboosters are either klystron tubes or solid state.
SC Super-Conducting.
SC Super Computing (as in SC04, SC05, etc.)
SC DOE Office of Science (Government organizational code).
SC Safety Collimator.
SCA Scientific Computing Applications department (SLAC).
SCA SuperConformal Algebra
SCADA Supervisory Control And Data Acquisition.
SCAG State of California Association of Governments.
SCALLA Structured Cluster Architecture for Low Latency Access.
Scanning Wire Ion Chamber See SWIC.
SCAP Security Content Automation Protocol.
SCAQMD South Coast Air Quality Management District.
SCAS Stanford Contractor Assurance System.
Scavenger See Scavenger Beam.
Scavenger Beam The high-current electron beam sent to the target to produce positrons. It is called Scavenger
because it uses the leftover RF power after the main collision bunches are accelerated.
Scavengy A multiknob used to tune the energy of the scavenger beam. This is done by varying the phase of
Subboosters 17 and 18.
SCBA Self-Contained Breathing Apparatus.
SCCDPH Santa Clara County Department of Public Health.
SCCS Scientific Computing and Computing Services.
sCDM standard Cold Dark Matter
SCDMS Super Cryogenic Dark Matter Search
SC&EA Strategic Communications & External Affairs (SLAC)
SCET Soft Collinear Effective Theory.
SCFF Super Conducting Final Focus.
SCFT SuperConformal Field Theory
SCGF DOE Office of Science (SC) Graduate Fellowship program.
SCGSR DOE Office of Science (SC) Graduate Student Research program.
SciDAC Scientific Discovery through Advanced Computing. (DOE)
Scintillator A type of detector that makes use of the flash of light emitted by the electrons in an excited
atom falling back to their normal energy or `ground' state after having been excited by a passing particle.
Used in conjunction with a photomultiplier to produces a measurable current for each `scintillation.' The most
common scintillator material is plastic.
SCIPP Santa Cruz Institute for Particle Physics.
SCL Safety Check List.
SCM SuperConducting Magnet
SCM Supply Chain Management.
SCOAP3 Sponsoring Consortium for Open Access Publishing in Particle Physics.
SCORM Sharable Content Object Reference Model.
SCP Site Characterization Plan.
SCPD Stanford Center for Professional Development
SCR Silicon Controlled Rectifier. A solid-state electronic switch which holds off voltage until its gate
lead is pulsed, which then causes conduction until the device is back biased, or zero biased. SCRs are used
frequently as the main rectifiers in large, variable current, regulated power supplies.
Scraper See Collimator.
SCRF SuperConducting RadioFrequency.
SCROD School Cosmic Ray Outreach Detector.
SCS Scientific Computing Systems (or, historically, SLAC Computing Services)
SCSC Scientific Computing Steering Committee.
SCSI Small Computer System Interface.
SCSS SPring-8 Compact SASE Source (Japan).
SCT SemiConductor Tracker.
SCT Superconducting Triplets. The superconducting quadrupoles in Final Focus.
SC-TBD Secondary Containment - Technical Basis Document.
SCUBA Submillimeter Common User Bolometer Array.
SCVPGM Sagittal focusing and converging beam
SD Surface Detector (Auger Observatory).
SD Silicon Detector.
SD Schwinger-Dyson.
SD Sextupole Defocusing.
SDE Schwinger-Dyson Equations
SDF Sludge-Derived Fuel.
SDG SelfDual Gravity
SDI State Disability Insurance.
SDL Subbooster Drive Line. The Rf line from any given subbooster to the 8 klystron modulator stations
in the particular sector it drives.
SDLC System Development LifeCycle. Also Software Development LifeCycle.
SDLC Serial Data Link Controller.
SDLCQ Supersymmetric Discrete Light Cone Quantization
SDM Software Development and Maintenance.
SDMP injector Spectrometer DuMP. (SLAC)
SDN Science Data Network. (DOE)
SDO Solar Dynamics Observatory.
SDOHS State Department of Health Services, California. It is also known as CDHS, DHS, and DOHS.
SDP Permanent Sextupole - Defocusing.
SDR System Design Review
SDS SLAC Design Services.
SDS Safety Data Sheet.
SDSL Symmetric Digital Subscriber Line. A technology that allows high volumes of data, up to 3Mbps, to be
sent over existing conventional copper telephone lines.
SDSS Sloan Digital Sky Survey.
SDSS-II Sloan Digital Sky Survey-II.
SDWA Safe Drinking Water Act. (Federal)
SEABA Science Education Academy of Bay Area
Search Reset A PPS status obtained after a search and needed to put a PPS area in `No Access' mode. Search
reset buttons are located outside the PPS gates except for the BSY and the LINAC. The search team leader must
press a searched zone's search reset button at the same time that a similar button is depressed at MCC in
order to get `search status set' for any given zone, so that the `No Access' state can be achieved for that
zone, and beam brought through the zone.
SEC SECtor.
SecCM Security-focused Configuration Management.
SECO SEcondary Engine Cutoff. (NASA)
Secondary Emission Monitor See SEM.
Secondary Treatment The second step in most publicly owned waste treatment systems in which bacteria
consume the organic parts of the waste. It is accomplished by bringing together waste, bacteria, and oxygen
in trickling filters or in the activated sludge process. This treatment removes floating and settleable
solids and about 90 percent of the oxygen-demanding substances and suspended solids. Disinfection is the
final stage of secondary treatment. See Primary Waste Treatment and Tertiary Treatment.
SEC-SAXS Size Exclusion Chromatography SAXS
Security Crash A PPS incident which occurs when the PPS security of the machine is lost. It may be caused
by a person opening a secured door to a searched zone, or by an electrical failure in the PPS system.
SED Spectral Energy Distribution.
SED Stream EDitor. A powerful Unix command for modifying the information in a pipeline.
SEDA SLAC Engineering Document Archive
SEDAC Safety and Environmental Discussion Assistance Committee
SEDP Safety and Environmental Discussion Program.
SEE Satellite Energy Exchange.
Seeman Screen Profile Monitor screens at the end of the LINAC in sector 29 and 30. The beam is deflected by
pulsed kickers on to these screens. Named after their designer, John Seeman.
SEET SLAC Ergonomic Evaluation Team.
SEGUE Sloan Extension for Galactic Understanding and Exploration.
SEIS Supplemental Environmental Impact Statement.
SEIU Service Employees International Union.
SELEX SEgmented LargE X baryon spectrometer.
SEM Scanning Electron Microscope.
SEM Secondary Emission Monitor. The SEMs are thick metal plates insulated from ground. When struck by a beam,
these devices produce a shower of electrons from the plate. The plate then becomes positive and a signal is
extracted to the BCS racks.
SEM Site Engineering and Maintenance.
SEN Secretary of Energy Notice.
Sensitizer A substance which produces an allergic reaction.
SEP SEPtum.
SEPT SEPTum magnet.
Septa Plural of Septum.
Septum A magnet incorporating a partition with a strong field on one side and little or no field on the other.
It is used in combination with a kicker to bend one beam while leaving another undisturbed, usually in order
to inject and/or extract a beam from a storage ring. it can be either a vertical or horizontal bend. See Lambertson.
Septum Bump An orbit bump created around a septum magnet to move the beam path into the `no field' area of a
septum. Septum bumps are usually four magnet bumps, which allow control of the beam's angle as well as its
offset through the septum area.
SERA SLAC Emergency Relief Association.
SERC State Emergency Response Commission. (EPCRA)
SERG Science and Engineering Research Group (SU Libraries).
Serial Crate Controller See SCC.
SERPUKHOV SERPUKHOV proton synchrotron (76 GeV/c Plab).
SERPUKHOV UNK SERPUKHOV multi-TeV proton machine.
SERT SLAC Emergency Response Team.
Server A computer that shares its resources, such as printers and files, with other computers on the network.
An example of this is a Network Files System Server which shares its disk space with a workstation that does
not have a disk drive of its own.
SESAME Synchrotron-light for Experimental Science and Applications in the Middle East.
SETI Search for Extraterrestrial Intelligence. (Institute)
SEXT SEXTupole. A six-pole magnet used to eliminate chromatic aberrations in a beam transport system.
Sextupole See SEXT.
SF Sextupole Focusing.
SF Schroedinger functional
SFA Scientific Focus Area
SFF South Final Focus.
SFG Spectrometer Facilities Group.
SFM CERN split-field magnet.
SFMP Surplus Facilities Management Program of Strategic Facilities Master Plan.
SFR Star Formation Rate.
SFS Spent-Fuel Standard
SFT Permanent Sextupole - Focusing.
SG Safety Glasses, with wide shield, or Safety Goggles.
SG Sine-Gordon
SGD Soft Gamma-ray Detector. One of the planned components of ASTRO-H.
SGM Superon Graviton Model.
SGML Standard Generalized Markup Language. A system for organizing and tagging elements of a document.
See also XML.
SGR Soft Gamma Repeater
SHA Safety, Health and Assurance. (Dept. in ES&H)
SHAB Second Harmonic AfterBurner. (LCLS)
SHALA Stanford Health and Lifestyle Assessment.
SHAM Sample and Hold Module.
SHCDM Super-Hubble Cold Dark Matter.
SHDM Super-Heavy Dark Matter.
SHM Safe Hold Mode.
SHMET SHeet METal.
Shower Any multiplicative radiation effect whereby a particle `creates' two or more particles, each of which
creates two or more, etc. causing a `shower' of radiation from a few initial particles. Also, a cascade of
particles generated by pair production and bremsstrahlung radiation.
SHPO State Historic Preservation Office. (California)
SI System Integrator. (Computing)
SIAD Stanford Internal Audit Department.
SIAM Summary Interlock and Alarm Module
SIB Storage Interface Board.
Siberian Snake A term coined by Y.S. Derbenev and A. Kondralenko at the Institute of Nuclear Physics in
Novosibirsk, the Siberian Snake is a device to be inserted into the lattice of a circular accelerator to preserve
the polarization of a proton beam during the acceleration process.
SIC Standard Industrial Classification.
SID SLAC Institutional Database.
SiD Silicon Detector concept for the ILC.
SID # SLAC Institutional Database Number. A number given to every employee, contractor, or other worker at SLAC.
Formerly called the BinKey (during SLAC's mainframe days).
SIDIS SemiInclusive Deep Inelastic Scattering.
SIEM Security Incident and Event Monitoring. (Computing)
Sierra Monitor A computerized hazardous gas analyzing station with 16 multiplexed input channels and a printer.
It is used to monitor oxygen deficiency in the pit and in the NRTL cryogenics system.
Sieve Collimator A special collimator used in CID to control beam current. The collimator has four or five
holes with various diameters and can be rotated for a desired aperture. Two of the apertures have multiple small
holes like a sieve, allowing from ten percent to 33 percent of the beam to get through.
SIGM Serpukhov CERN-IHEP magnetic spectrometer (SIGMA).
Sigma A statistical parameter referring to the standard deviation of a distribution where `one sigma' means one
standard deviation away from the median (the square root of the variance). It is used for a bunch of particles
approximated to a normal, or Gaussian distribution. For a normal distribution, 68 percent of the particles are
within `one sigma,' 95 percent are within `two sigmas' and 99.7 percent within `three sigmas.' In a storage
ring, the aperture should be at least eight sigmas for reasonable lifetimes.
Sigma The size (section) of a beam, assuming that the bunch shape is Gaussian and limited to one sigma.
Sigma Matrix A matrix description of the phase space distribution of a beam.
Sigma Phi The vertical angular divergence at the IP.
Sigma Theta Horizontal Angular divergence at the IP.
Sigma X The transverse size of the beam in the X, or horizontal direction.
Sigma Y The transverse size of the beam in the Y, or vertical direction.
Signal Words The words used on a pesticide label--`Danger,' `Warning,' `Caution'--to indicate the level of
toxicity of the chemicals.
Signal-to-Noise Ratio When used in reference to Usenet activity, `signal-to-noise ratio' describes the relation
between amount of actual information in a discussion, compared to their quantity. More often than not, there is
substantial activity in a newsgroup, but a very small number of those articles actually contain anything useful.
Signature The small, usually four-line message at the bottom of a piece of E-mail or a Usenet article.
In Unix, it is added by creating a file `.signature' in the user's home directory. Large signatures are a no-no.
SIIMS SLAC Issues & Improvements Management System
SIL Safety Integrity Level.
SILI Silicon detector.
Silicon Controlled Rectifier See SCR.
SIMES Stanford Institute for Materials and Energy Sciences. (Formerly XL AM).
SIMP Strongly Interacting Massive Particle
SIMPLE 2000 Superheated Instrument for Massive ParticLE searches
Simple Mail Transfer Protocol See SMTP.
Simple Network Management Protocol See SNMP.
Single Beam Dumper A pulsed magnet in the 51 or 52 line that kicks the beam to a dump. Used to dump the
beam whenever the arcs are not ready. Some MPS trips cause the Single Beam Dumper to fire.
SINGS SIRTF / Spitzer Infrared Nearby Galaxies Survey.
Singularity A point with infinite density where space-time is infinitely curved a boundary or edge to space-time.
SINQ Swiss Spallation Neutron Source (Paul Scherer Institute)
SIOP Serial Input -- Operating Parallel.
SIP State Implementation Plan. (from CAA)
SiPIN Silicon Positive-Intrinsic-Negative photodiodes.
SiPM Silicon PhotoMultiplier.
SISGR Single-Investigator and Small-Group Research. (DOE)
SISSA Scuola Internatizionale Superiore du Studi Avanzati. (Trieste, Italy)
SIT Saitama Institute of Technology. (Japan)
SIT South Injection Tunnel. The positron transport line going from the BSY to PEP. Also: South Injection Transport.
SIT System Integration Test. (OCIO) COMPUTING
SITE Superfund Innovative Technology Evaluation Program. (from CERCLA)
SiW Silicon tungsten group (ILC).
SIXA Silicon X-ray Array
SK SuperKamiokande.
SKA Square Kilometer Array.
SKdV Supersymmetric Korteweg-de Vries
Skew Quad A quadrupole whose axis is rotated 45 degrees. This puts the coils vertical and horizontal instead
of `X' shaped as in a regular quadrupole.
Skyshine Air-scattered radiation.
SL energy defining SLit, high Z slit.
SL SuperLattices
SLA Service Level Agreement
SLAC Stanford Labor Action Coalition.
SLAC ScaphoLunate Advanced Collapse.(Wrist condition: see http://www.medmedia.com/ooa1/98.htm)
SLAC SLAC National Accelerator Laboratory. (Formerly Stanford Linear Accelerator Center.)
SLA C Energy Doubler See SLED.
SLAC Orange A portable ionization chamber survey meter designed by the SLAC Health Physics
Group and fabricated onsite.
SLAC Standard Operating Procedure See SOP.
SLAC Web page a Web Page that is served by a SLAC computer.
SLACERT SLAC Emergency Response Team.
SLACNET SLAC NETwork.
SLACronym Acronym / lingo used at SLAC.
SLACS Sloan Lens ACS survey. An efficient Hubble Space Telescope (HST) snapshot imaging survey for new galaxy-scale strong
gravitational lenses.
SLCCC Systems of Laboratories Computer Coordinating Committee. (DOE)
SLDA Superfluid Local Density Approximation.
SLED SLAC Energy Doubler. A system of RF resonant cavities on the output of each klystron which doubles the strength of the
electric field delivered to the LINAC. It works by storing the front, or leading half of the klystron pulse, and then adding that
energy to the rear, or trailing half of the pulse to get a pulse which is about half as long but twice as strong in peak power.
'Sledding' the linac has enabled it to double its total accelerating range from about 30 GeV to 60 GeV at a fraction of the
cost of doubling the number of klystrons.
SLED II SLAC Energy Doubler, version 2. Upgrade to SLED system designed by Sami Tantawi.
SLEGS Shanghai Laser Electron Gamma Source.
Sleuth A model-independent search strategy for new high-pT physics, developed by physicist Bruce Knuteson and used by the
D0 collaboration in Tevatron Run I. Initially known as Sherlock, the name was changed to Sleuth to avoid trademark
litigation.
SLEW Stanford-SLAC Engagement Working Group
sLHC Super LHC.
SLI Science Laboratory Infrastructure.
SLIC GEANT4-based flexible full-detector simulation program. Replaces LCDG4.
SLIP Serial Line IP. A protocol that allows a computer to use the Internet protocols and become an Internet member
with a standard phone line and a high-speed modem. Being superseded by PPP but still used.
SLM Synchrotron Light Monitor.
Slow Valve See VAT Valve.
SLS Swiss Light Source, a synchrotron radiation facility at the Paul Scherrer Institute (Switzerland).
SLSO Systems Laser Safety Officer.
SLTR South LINAC To Ring.
SLUM Silicon LUMinosity tracker.
SLUO SLAC Users Organization (previously SLAC-LBL Users Organization)
SLV-III Satellite Launch Vehicle-III.(India)
SM Standard Model.
Small Angle Monitor See Mini Sam.
Small Power Supply See SMPS.
SMART Safety MAnagement Records Tool. (database)
Smart Analog Module See SAM.
SMART goals Specific, Measurable, Attainable (or aligned), Relevant (results-oriented or realistic), Time-bound
goals for job performance.
SMARTS Small and Moderate Aperture Research Telescope System.
SMASH-ML Solving Materials And Structures by Heuristic Machine Learning
SMB Structural Molecular Biology.
SMBH Super Massive Black Hole.
SMC Spin Muon Collaboration (CERN) P
SMC Small Magellanic Cloud
SMCT Semiconductor Multiple-Compton Telescope.
SMDS Switched Multimegabit Data Service. An emerging high-speed networking technology to be offered by the telephone
companies in the U.S.
SME Subject Matter Expert.
SME Standard Model Extension.
SMEX SMall EXplorer (NASA Program).
SMG Standard Model Gauge group
SML Standby Maintenance List (Artemis).
SM-LWFA Self-Modulated Laser Wakefield Acceleration
SMMC Shell Model Monte Carlo
Smog Air pollution associated with oxidants.
SMRT Single Molecule Real Time. Pacific Biosciences trademark term for its biological analysis platform.
SMS Surface and Materials Science department (Formerly Physical Electronics).
SMS Safety Management System.(SLAC's ISMS program.)
SMT Senior Management Team.
SMT SAM Tester.
SMTF Superconducting Module Test Facility. (ILC)
SMTP Simple Mail Transfer Protocol. The Internet standard protocol for transferring electronic mail messages from
one computer to another. SMTP specifies how two mail systems interact and the format of control messages
they exchange to transfer mail.
SN ServiceNow.
SN SuperNova
SN1987A SuperNova 1987A.
SNA Systems Network Architecture. The proprietary network architecture of IBM.
SNAP SuperNova Acceleration Probe/Program. See JDEM.
SNARL Suggested No Adverse Response Level.
SNBO SuperNova Burst Observatory.
SND Spherical Nonmagnetic Detector
SNe SuperNovae.
SNF Stanford Nanofabrication Facility.
SNI Super Nova Type I
SNIa Type Ia SuperNovae.
SNIC SLAC-Novosibirsk Instrumentation Conference.
SNIF Secret Neutrino Interactions Finder.
SNII Type II SuperNovae.
SNLO Select Non-Linear Optics.
SNMP Simple Network Management Protocol. The network management protocol of choice for
TCP/IP-based internets.
SNO Subdury Neutrino Observatory (Canada). Also referred to as SNOLab.
SNOLAB Sudbury Neutrino Observatory LABoratory. (Canada)
SNR SuperNova Remnant
SNS Spallation Neutron Source. (Oak Ridge)
SNUG Synchrotron Neutron User Group. PHOTON
SNUR Significant New Use Rule. (from TSCA)
SO Secretarial Officer.
SO Safety Officer (institutional).
SO2 Sulfur Dioxide. A heavy, pungent, colorless, gaseous air pollutant formed primarily by industrial fossil-fuel
combustion processes.
SOC Science Operation Center (GLAST-NASA).
SOC Synthetic Organic Chemical.
SOC Safety Overview Committee.
SODA SLAC Online Drawing Access. (database) Obsolete: see SEDA.
Soft Bend A weak bend magnet, usually the last bend in a string before a target or interaction point, which, due
to its lower strength, creates less synchrotron radiation noise on the detection apparatus.
SOG Science Operations Group.(GLAST)
SOI Silicon-On-Insulator.
SOIC SSRL Operator In Charge.
SOLEIL Source Optimisee de Lumiere d'Energie Intermediaire du Lure. Third-generation synchrotron
radiation source in France.
Solid State Subbooster See SSSB.
Solubility The ability of a solid, liquid, or gas to dissolve in a solvent (usually expressed in water). Not related
to density or specific gravity.
Solvent A substance (usually liquid) capable of dissolving or dispersing one or more
other substances.
SOM Same-Order Mode.
SOML Steward Observatory Mirror Laboratory (Arizona).
SON Safety Orientation for Non-employees (ES&H)
SOP Standard Operating Procedure. SOP numbers are given to SLAC documents on various subjects.
SOR Synchrotron Orbital Radiation.
Sorbent A material that attracts and holds another material.
SORI Safety and Operational Reliability Improvements project.(Sometimes written as S&ORI)
Sorption The action of soaking up or attracting substances. A process used in many pollution
control systems.
SOUD SOUDan underground detector (MN, USA)
SOUDAN 2 One-kiloton underground detector in former iron mine in Soudan (MN, USA)
Source The area or device where a beam of particles originates, as in `positron source.'
SOW Statement Of Work.
Space Charge The repulsive Coulomb forces in a bunch of particles of the same polarity.
SPAFOA Superconducting Particle Accelerator Forum of the Americas.
SPAG Standards Promotion and Application Group. A group of European OSI manufacturers which chooses option
subsets and publishes these in a `Guide to the Use of Standards' (GUS).
Spallation A process in which a beam of protons smashes into a target, releasing a flood of neutrons.
SPATS South Pole Acoustic Test Setup.
SPC Scientific Policy Committee. From 2005-2008, the SLAC Policy Committee.
SPCC Spill Prevention, Countermeasures and Control plan.
SPD Strategic Projects Division.(LCLS)
SPEAR Stanford Positron Electron Accelerating Ring. Created in 1970 out of the SLAC operating budget
(it was not separately funded). Originally designed in 1963 as a single-ring machine called the SLAC Electron-Positron
Colliding Beam Storage Ring, the design was upgraded in 1969 and a double-ring asymmetric machine, the 'Stanford
Positron Electron Asymmetric Rings' (hence, SPEAR)was proposed. When funding failed to materialize, the project was
scaled back to a single, racetrack-ring configuration and the acronym was converted to the machine's one-word name.
(For a time the scaled-back, single-ring revised design was referred to as 'SPEAR 1/2', but the name did not stick.)
Many high-energy physics experiments have been conducted in this facility, two of which have earned Nobel prizes: one
for the discovery of the Psi/J particle, or Charmed Quark in 1974, and a second for the discovery of the Tau lepton
in 1975. SPEAR is now being used as a synchrotron light source by many experimenters from all over the world, and it
is probably the most useful high-energy physics machine ever built.
SPEAR 3 Planned upgrade of SPEAR that proposes to replace the ring with a new set of magnets and other components which
would improve its performance as a light source.
SPEC SPECification.
SPEC Spectrometer.
Special Review Formerly known as Rebuttable Presumption Against Registration (RPAR), this is the regulatory process
through which existing pesticides suspected of posing unreasonable risks to human health, non-target organisms, or
the environment are referred for review by EPA. The review requires an intensive risk/benefit analysis with
opportunity for public comment. If the risk of any use of a pesticide is found to outweigh social and economic
benefits, regulatory actions--ranging from label revisions and use-restriction to cancellation or suspended
registration--can be initiated.
Specific Gravity The ratio of the density of a substance to the density of water.
SPECT Single-Photon Emission Computer Tomography.
SPECT SPECTrometer line.
Spectrometer Energy Spectrometer. A device to measure the energy spectrum of a beam. Sometimes call a Mass
Spectrometer. A beam of a given mass and energy is bent around a noodle shaped bend magnet into a detector or
counter. Only particles of the required or specified mass and velocity (energy) will be bent into the target by
the carefully regulated field of the bend magnet.
SPi Smart Plug-in (HP integrated module used for Oracle PeopleSoft Enterprise application)
SPICA SPace Infrared telescope for Cosmology and Astrophysics.
SPIE International Society for Optical Engineering.
Spill Monitor An ion chamber near the beampipe designed to show the operators the relative amount of beam being
lost by `scraping' on the inside of the beampipe, or on any upstream device.
Spill Response Environmental Safety and Health procedure for responding to the accidental overflow of hazardous
or non-hazardous material.
SPIM Selective Plane Illumination Microscope.
Spin Rotator A solenoid magnet used to rotate the spin axis of electrons in a polarized beam.
SPIRAL Système de Production d'Ions Radioactifs Accélérés en Ligne. (System for the Production of Radioactive
Ions Accelerated on Line) Caen, France.
SPL Single Purchase Limit.
SPL Superconducting Proton Linac (CERN-proposed).
SPL Sample Preparation Laboratories (LCLS)
SPOF Single Point Of Failure.
Spoiler A device to blow up the beam size. A spoiler is used in front of the positron target. Spoilers are used
to reduce the density of energy deposited on a dump, stopper, or other target. Instead of the tightly focused
beam burning a hole in the dump, stopper, or target, the spoiler `spreads the misery around,' distributing the
energy over the whole frontal area of the device.
Spot The bright mark made by the beam on a profile monitor screen. Generally, operators try to reduce the size
of the spot and give it a good shape by adjusting machine parameters that are upstream of the screen.
SPP Strategic Partnership Projects
SPPC SPoolPieCe.
SPPS Sub-Picosecond Particle Source (formerly Sub-Picosecond Photon Source).
SPPS Super antiProton Proton Synchrotron (CERN).
SPring-8 Super Photon ring-8 GeV. Synchrotron radiation source at Harima, Japan.
SPRL State Priority Ranking List.
SPs Service Packs (computing).
SPS Super Proton Synchrotron (CERN)
SPS+ Superconducting SPS.
SPSC Super Proton Synchrotron Committee (CERN).
SPSC SuperProton-Synchrotron Collider.
SPSCL Set-up Phase Safety Checklist. (LCLS)
SPTpol South Pole Telescope polarization-sensitive microwave camera.
SPTRM SPecTRoMeter.
SPTT SPuTTering.
SPY Secondary Particle Yield (CERN experiment)
SQ Sub-scale Quadrupole.
SQCD Supersymmetric QCD
SQED Supersymmetric Quantum ElectroDynamics.
SQF Safety Qualification Form.
SQG Small Quantity Generator. (from RCRA)
SQL Structured Query Language. The international standard language for defining and accessing
relational databases.
SQM Strange Quark Matter.
SQM Supersymmetric Quantum Mechanics.
SQN Strange Quark Nuggets.
SQS Space of Quantum States.
SQUID Superconducting QUantum Interference Device.
SR Sponsored Research
SR Synchrotron Radiation.
SR SteRadian.
SR Shielded Room. A PPS Item.
SR2A Synchrotron Radiation in Art and Archeology (workshop).
SRB Storage Resource Broker (grid software).
SRB South Reverse Bend. See RB.
SRCF Stanford Research Computing Facility.
SRCF-II Stanford Research Computing Facility annex (planned construction)
SRD Science, Research and Development division. (LCLS)
SRF Superconducting RF.
SRF Superconducting Radio-Frequency.
SRI Synchrotron Radiation Instrumentation
SRL Synchrotron Radiation Laboratory (Japan).
SRMS Synchrotron Radiation in Materials Science (conference).
SRR Site Recommendation Report.
SRR System Requirements Review
SRS Savannah River Site. (DOE)
SRS Synchrotron Radiation Source
SRTL South Ring To LINAC.
SRX Sub-micron Resolution X-ray spectroscopy.
SS Suspended Solids.
SS Source and Special
SSA Single Spin Asymmetries.
SSB Spontaneous Symmetry Breaking.
SSB Science Support Building. See SUSB.
S-SBM Strangeness-including Statistical Bootstrap Model
SSC Stop-Start-Continue.
SSD Silicon Strip Detector. (GLAST)
SSE Stars and Stellar Evolution.
SSI SLAC Summer Institute.
SSJ Single-Source Justification.
SSL Secure Sockets Layer. A protocol developed by Netscape for transmitting private documents via the internet. SSL
works by using a private key to encrypt data that is transferred over the SSL connection. Many web browsers support SSL,
and many Web sites use the protocol to obtain confidential user information,
such as credit card numbers. Web pages that require an SSL connection start with https instead of http.
SSM Supersymmetric Standard Model
SSMB Steady State Micro Bunching
SSO Single Sign On
SSO SLAC Site Office. (DOE)
SSOW SLAC Statement of Work.
SSP Shared Services Package (Microsoft).
SSP Site Safety Plan.
SSP System Security Plan. (OCIO)
SSPM Solid-State PhotoMultiplier
SSPR Self-Service Password Reset.
SSRC Synchrotron Radiation Research Center. (China)
SSRF Shanghai Synchrotron Radiation Facility.
SSRL Stanford Synchrotron Radiation Lightsource. A division of SLAC which does experiments with synchrotron light
generated by the SPEAR storage ring. The synchrotron light produced by the SPEAR ring is a relatively narrow bandwidth,
`hard' X-Ray spectrum that is very useful in medical research, as well as in crystallography. (Formerly Stanford
Synchrotron Radiation Laboratory 1977-2008, and Stanford Synchrotron Radiation Project 1973-1977.)
SSRLUOEC SSRL Users' Organization Executive Committee.
SSRO SLAC Sponsored Research Office.
SSRP Stanford Synchrotron Radiation Project (1973-1977). Became SSRL in 1977.
SSSB Solid State SuBbooster. The subboosters driving some of the klystrons are solid state (ex. K02, EP02, Rings).
SSSP Site-Specific Safety Plan.
SSUN SLAC, Stanford University, NREL. (SIMES)
SSUSY Second derivative SUperSYmmetry.
STA SLAC Training Assessment. A process matching training with hazards an individual faces in his/her work.
STA Science and Technology Agency. Japanese government agency which, along with the Ministry of Education,
Science, Sports and Culture (Monbusho) funds big science in Japan.
STACEE Solar Tower Atmospheric Cherenkov Effect Experiment. (Sandia)
Standardization The process of cycling magnet currents through a preset pattern to establish a known hysteresis point
in the iron of each magnet. This gives any particular magnet field configuration the necessary repeatability to be
useful in beam operations.
Standards Prescriptive norms which govern action and actual limits on the amount of pollutants or emissions produced.
EPA, under most of its responsibilities, establishes minimum standards. States are allowed to be stricter.
Standards Promotion and Application Group See SPAG.
Standby See STB.
Standby Maintenance List A waiting maintenance list updated every morning at the Maintenance Meeting and
posted near the MCC door. The list includes the problems, the area, the entry needs or not, and the person to contact.
Standby Timing The continuous timing and pulsing of a kicker magnet or klystron even when no beam code triggers
are present. The Standby time is 15 to 50 microseconds after beam time and is different for each sector to avoid
acceleration of dark current. The stations need to be pulsed on standby to keep them warmed up so they will be in
time and at the right energy when they are actually used to accelerate the beam.
STANFORD Positron Electron Accelerating Ring See SPEAR.
Stanford Synchrotron Radiation Laboratory See SSRL.
STAP Staff Training Assistance Program. (Stanford University)
STAR Scientific and Technical Abstracts Reports.
STAR Science Teachers And Researchers. (SLAC, CSU, Bechtel)
STAR Solenoidal Tracker At RHIC (BNL)
STAR Stop Think, Act, Review
Star Network LAN in which multiple workstations are connected to a central server. All communications must be
routed through the central server.
STARE Survey for Transient Astronomical Radio transmission
STARS Stanford Training And Registration System
START Scintillation Tile with mrs Apd light ReadouT.
START Safety Toward Avoiding Risk Today.
Station Usually refers to one of the klystrons of the LINAC, together with its modulator and other auxiliary devices
necessary for operation.
Status Display Summary See SDS.
STAU Supersymmetric TAU
STB Standby. A klystron CUD message indicating a poor or bad standby timing result. See Standby Timing.
STB Simple Timing Buffer. A CAMAC timing module which converts differential MECL timing backplane signals to
front panel NIM pulses. Used with a PDU.
STCC Standard Transportation Commodity Code.
Steer To guide a beam through its preferred optical path using the available corrector magnets and trim windings
allocated for that purpose. Since upstream changes in steering magnify effects the further downstream you go,
steering is usually done with the aid of computer programs based on mathematical models of the lattice. These
are called `Autosteering' programs.
STELLA Staged Electron Laser Acceleration. (Brookhaven)
STEM Science Technology Education and Math.
Stepper Motor Controller See SMC.
STF Superconducting rf Test Facility (KEK).
STFC Science and Technology Facilities Council. (UK)
STI Steel Tank Institute.
STI Scientific and Technical Information.
STIC Small angle TIle Calorimeter
STIRAP STImulated Raman Adiabatic Passage
STLC Soluble Threshold Limit Concentration. (CCR Title 22)
Stochastic resonance A nonlinear phenomenon in which random noise optimizes a system's response to a
weak signal.
STOP A trigger used to control the output of the thermionic gun in the injector by changing the bias on the grid.
Trigger time is converted to a bias voltage.
Stopper A PPS device used to stop the beam, usually by allowing a heavy metal slug to pivot
into the beam's path.
STORI an International Conference on Nuclear Physics at Storage Rings, originally called the Symposium on Nuclear
Physics at Storage Rings.
STP Standard Temperature and Pressure.
STPR STOPPER.
STR Special Theory of Relativity
STRAW Thin walled tube chambers.
Streak Camera A device that measures the time distribution of a light pulse. Used to measure bunch length. Very fast
pulses of the order of a nanosecond or less can be measured with a Streak Camera.
Strict Liability Holds a party responsible for damages irrespective of the amount of care taken in handling
a hazardous substance.
STRIPES Strategic Integrated Procurement Enterprise System (DOE)
STRN Standard Technical Report Number.
STRP Staff Tuition Reimbursement Program (Stanford University).
Structured Query Language See SQL.
STTR Small business Technology TransfeR. (US Gov't)
STXM Scanning Transmission X-ray Microscope.
SU Stanford University.
SU-17A Employee First Report of Injury form
Subbooster See SBST.
Subbooster Drive Line See SDL.
Subbooster Interface See SBI.
Subharmonic Buncher See SHB.
Subtitle 1 The part of RCRA which pertains to the storage of petroleum products and hazardous substances, other
than wastes, in underground tanks.
Subtitle C The part of RCRA which pertains to the management of hazardous waste.
SUD Safe Use Determination.
SUGRA SUperGRAvity
Sulfur Dioxide See SO2.
SULI Science Undergraduate Laboratory Internship. (Formerly: SLAC Undergraduate Laboratory Internship)
Summarize To encapsulate a number of responses into one coherent, usable message. Often done on controlled
mailing lists or active newsgroups, to help reduce bandwidth.
SUMMIT Stanford University Medical Media and Information Technology.
SUNCAT SUstainable eNergy through CATalysis. (SLAC Photon Science initiative)
SUNET Stanford University NETwork.
Sun's Network Information Service See NIS.
SUOH Stanford University OverHead.
Superfish A modeling program used for CID which includes the S-BAND buncher and K02. It is able to calculate
the field in a cavity.
Superfund See CERCLA.
Supergravity An enrichment of ordinary general relativity in which the space/ time coordinates are fermionic
as well as bosonic. It is an up- dating of general relativity to include fermions just as supersymmetry is an
updating of special relativity to take into account that fermions exist.
SuperKamiokande A neutrino detector built in Japan to observe neutrinos from the Sun and supernovae. The detector
is a 50,000 ton water tank that is 41 meters high, 39 meters wide, and surrounded by 11,200 giant photomultiplier
tubes. The tubes detect the flashes of Cherenkov radiation produced when the neutrinos interact with the water.
The detector is located in a lead-zinc mine under 1000 meters of rock, which filter out the background cosmic rays.
Supersymmetry A conjectured symmetry between fermions and bosons. Two- dimensional supersymmetry emerged
historically from Pierre Ramond's discovery in 1970 of how to incorporate fermions into string theory.
Supersymmetry was formulated as a four-dimensional symmetry by Julius Wess and Bruno Zumino in 1974. It was
also conceived independently by Yuri Gol'fand and Eugeny Likhtman in 1971.
SURA Southeastern Universities Research Association.
SURF Sanford Underground Research Facility (Lead, South Dakota)
SUSB Science and User Support Building.
SUSY SUperSymmetrY.
SUSYM SUperSymmetric Yang-Mills.
SUTI Sensitive Unclassified Technical Information
Suzaku Astro-E2 / ASTRO-EII. Renamed Suzaku (Red Bird) in July 2005.
SV Schedule Variance.
SV Small Velocity
SVAC Science Verification And Calibration. (GLAST)
SVD Singular Value Decomposition
SVT Silicon Vertex Tracker.
SW Solid Waste.
SW Seiberg-Witten
SWAA Satellite Waste Accumulation Area.
SWAT Solid Waste Assessment Test. (CGC Sec. 66796.53, 66796.54, CWC Sec. 1 3273)
SWG Science Working Group.
SWG Space Working Group (SLAC).
SWIC Scanning Wire Ion Chamber. A precise beam position measuring device used to calculate beam energy.
Swift-BAT Swift Burst Alert Telescope. (NASA-Goddard)
Switched Multimegabit Data Service See SMDS.
SWKB Supersymmetric Wentzel-Kramers-Brillouin
SWMB Solid Waste Management Board (aka CWMB).
SWMR Single-Writer Multiple-Reader.
SWOPSI Stanford Workshops On Political and Social Issues.
SWOT Strengths, Weaknesses, Opportunities and Threats.
SWP Safety Watch Person.
SWPPP Storm Water Pollution Prevention Plan.
SWRCB State Water Resources Control Board. (California)
SXNS Surface X-ray and Neutron Scattering.
SXR Soft X-Ray materials science instrument. (LCLS)
SXRD Synchrotron-based surface X-Ray Diffraction.
SXRSS Soft X-Ray Self Seeding.
SYM Supersymmetric Yang-Mills
Synchronous Data Communications in which transmissions are sent at a fixed rate, with the sending and receiving
devices synchronized.
Synchrotron Feedback A damping ring RF feedback system which regulates the longitudinal beam oscillations due to
the RF driving forces.
Synchrotron Light See Synchrotron Radiation.
Synchrotron Oscillation A longitudinal oscillation induced in an accelerated bunch by the RF driving forces imparted
to the bunch by the cavities.
Synchrotron Radiation When a charged particle such as an electron or positron is bent in a magnetic field, it loses
energy in the form of photons (light) which are given off in a direction tangential to the curved path of the charged
particle. These photons are called Synchrotron Radiation after the high energy physics machine where they were first
observed. The photon energy increases with the 4th power of the beam energy and decreases with the square of the
radius of curvature. Synchrotron light, or X-rays, are used for beam observation purposes, for the study of the
structure of matter, and for medical research. See also SPEAR.
Synergism The cooperative interaction of two or more chemicals or other phenomena producing a greater total
effect than the sum of their individual effects.
Systems Network Architecture See SNA.
SYZ Strominger-Yau-Zaslow.
SZ Sunyaev-Zeldovich
SZE Sunyaev-Zel'dovich Effect.
Back to top
T&DF Trigger & Data Flow system (GLAST).
T(c ) Critical Temperature (for superconductors).
T/R Transmit/Receive.
T2K Tokai to Kamioka (KEK experiment).
TA Test Accelerator.
TAC Toxic Air Contaminant. (CH&SC Sec. 39650 et seq)
TAC Texas Accelerator Center.
TAC Time to Amplitude or Analog Converter.
TAC Technical Advisory Committee (Linac Coherent Light Source).
TAG Temporal Axial Gauge
Taleo Enterprise management staffing software in use at SLAC.
TAMA Interferometric gravitational-wave detector. (Japan)
TANGO an object oriented control system based on CORBA.
TAOS Taiwanese American Occultation Survey.
TAPS Two-Arm Photon Spectrometer
TARC Third-Party Activity Review Committee or The Activity Review Committee reviews and approves activities with external entities (SLAC).
Target Coil The coil around the positron target.
TARLA Turkish Accelerator and Radiation Laboratory at Ankara.
TASI Theoretical Advanced Study Institute.
TASS TASSo detector (DESY).
Tau Charm Factory See TCF.
Tauon Tau-Lepton.
TB Two Boson
TBA Two-Beam Accelerator.
TBA Thermodynamic Bethe Ansatz
TBD Technical Basis Document (ES&H).
TBR To Be Replaced. A klystron status mode indicating the klystron tube needs replacement.
TC Toxicity Characteristics.
Tc critical Temperature (in superconductivity).
TC Target Changer multiple, beryllium, single foil, liquid H2or D2
TCA 1,1,1-Trichloroethane.
TCAV Transverse CAVity. (LCLS)
TCE Trichloroethylene.
TCF Tau Charm Factory. A very high-luminosity electron- positron collider with a total energy of about
3 to 4.5 GeV. This energy range enables the copious production of tau leptons and charmed mesons by electron-positron
annihilation with a minimum of background from other annihilation processes.
TCLP Toxicity Characteristic Leaching Procedure. (See 40 CFR, Part 268, Appendix l.)
tcmIS total chemical Information System.
TCP Transmission Control Protocol. The major transport protocol in the Internet suite of protocols providing
reliable, connection- oriented, full-duplex streams. Uses IP for delivery.
TCP/IP Transmission Control Protocol/Internet Protocol. A common computer data standard combining transport and
network level protocols. Often used with Ethernet as a physical layer protocol.
TCPIP See TCP/IP
TCSA Truncated Conformal Space Approach
TCSG A secondary collimator at the LHC.
TCW ThermoCouple Wire.
TD Transportation Department.
TDAQ Week Trigger and Data AQuisition Week. (Atlas -- at SLAC)
TDGL Time-Dependent Ginzburg-Landau
TDHF Time-Dependent Hartree-Fock.
TDM Transportation Demand Management.
TDP Technical Design Phase. (ILC)
TDP-1 Technical Design Phase 1 (ILC).
TDR Technical Design Report.
TDRSS Tracking and Data Relay Satellite System. (GLAST)
TEA Triethylamine
TEAM Transformational Energy Action Management.(DOE Initiative)
TEC Total Estimated Cost.
TEDE Total Effective Dose Equivalent.
TEK Twisted Euguchi-Kawai.
Telnet The Internet standard protocol for remote terminal connection service. Telnet allows a user at one site to
interact with a remote timesharing system at another site as if the user's terminal were connected directly to the
remote computer.
TEM Tower Electronics Module. (GLAST)
Ten Finger Box A section in the DRIP vacuum chamber where ten beam pipes are connected together.
TERA Thunderstorm Energetic Radiation Array. (University of Florida/ Florida Tech)
TERA TErapia con Radiazioni Adroniche, or Therapy with Hadronic Radiations. part of the Italian foundation for
hadron therapy, Fondazione per Adroterapia OncologIca.
Teratogenic Capable of producing congenital malformations.
Terminal An interactive station connected to a host computer. Can be classified into four categories: visual
display, hard copy, graphics and emulation. A terminal emulation can be done with a microcomputer and the appropriate
software. Terminals usually consist of a keyboard, modem or network connection, and video display.
Terminal Server A small, specialized, networked computer that connects many terminals to a LAN through one network
connection. Any user on the network can then telnet to various network hosts. A terminal server can also connect
many networks' users to its asynchronous ports.
TERR Transmitter ERRor.
Tertiary Treatment Advanced cleaning of wastewater that goes beyond the secondary or biological stage. It
removes nutrients such as phosphorus and nitrogen and most BOD and suspended solids.
TES Transition Edge Sensors.
TESLA TeV Energy Superconducting Linear Accelerator (DESY)
Tesla The standard unit of magnetic field strength. A typical non-superconducting magnet has a maximum strength
of approximately two tesla.
TESLA-XFEL TeV Energy Superconducting Linear Accelerator X-Ray Free-Electron Laser. (DESY)
TESS Transitory Exoplanet Survey Satellite.
TeV Tera Electron Volt (1 trillion electron volts).
TEX TeX (pronounced `tek'). A text processing program, available for many computers, to create and format
text output. TeX is a free typesetting system designed by Stanford's Donald Knuth.
TeX macro A TeX command that invokes a predefined set of other TeX commands, which may contain other
TeX macros or TeX primitive commands.
TeX primitive A command native to TeX, that is, a command that TeX recognizes when no extra macros are defined.
TFBK Timing FeedBacK. A feedback used to stabilize kicker timing.
TFD Thermo Field Dynamics
TFT Topological Field Theory.
TFXA Time Focused Xtal Analyzer
TG Tangential Group
TGAS Trigger Gate And Synchronization. A module which allows continuous gating of the gun trigger in steps
of a few picoseconds. It uses the 178.5 MHz RF synchronized with the 119 MHz of aPDU to allow fine adjustments.
TGC Thin-Gap Chambers.
TGC Triple Gauge Couplings
TGM Toroidal Grating Monochromator
TGP Tuition Grant Program. (Stanford)
THDM Two Higgs Doublet Model.
THEO THEOretical or heavily model-dependent result.
Thermocouple Reference Plane See TRP.
Thermoluminescent Dosimeter See TLD.
THI High intensity transport
THM TriHaloMethane.
THP THeoretical Physics. (SLAC)
Threshold Limit Value See TLV.
Threshold Planning Quantity See TPQ.
THY Theory.
Thyratron A gas filled tube used as a switching device for modulators and for kickers. The tube holds
off high voltage until its grid is pulsed, ionizing the gas, and allowing immediate high current flow. Its
solid state equivalent is the SCR, or silicon controlled rectifier. See SCR.
Thyratron Reservoir A device for regulating the ionization gas pressure in a thyratron.
THz TeraHertz.
TIC Time Interval Counter.
TID Technology and Innovation Directorate. (SLAC)
TIFF Tagged Information File Format.
TILC The International Linear Collider (workshop).
TIM Technical Interchange Meeting.
Time Reference See TREF.
Time Slot See TS.
Time Slot Separation The timing jitter or variance between beams on different time slots. It is caused by time
varying magnetic or electric fields not synchronous with the incoming AC phase.
Time to Digital Converter See TDC.
TIMES Theory Institute for Materials and Energy Sciences
Timing Feedback See TFBK.
TIPP Technology and Instrumentation in Particle Physics, (Conference)
Title 08 The title of the California Code of Regulations which contains regulations promulgated by Cal/OSHA
pertaining to worker safety and health.
Title 13 The title of the California Code of Regulations which contains regulations promulgated by the CHP
pertaining to the transport of hazardous materials.
Title 19 The title of the California Code of Regulations which contains regulations promulgated by OES
pertaining to business emergency plans, area plans, emergency spill notification, and community right-to-know.
Title 22 The title of the California Code of Regulations which contains regulations pertaining to hazardous
waste management and other related matters as promulgated by the CDHS.
Title 23 The title of the California Code of Regulations which contains regulations regarding
water protection (including underground tanks) as promulgated by the SWRCB.
Title 26 The title of the California Code of Regulations which contains excerpts from other titles
pertaining to toxics. This title was created as a convenience to the user. It contains no regulations which
are not also located within another of the first twenty-five titles.
TIU Tone Interrupt Unit. The MPS system uses a 20 to 60 KHz tone signal loop whose interruption by various
machine protection monitoring devices will cause the beam to trip off. The tone interrupt units are the interface
between the tone loop and these devices.
TIXEL TIme-resolving piXELated particle detector.
TKR silicon-strip detector TracKeR (GLAST)
TL Test Laboratory building.
TL Team Leader.
TLA Three-Letter Acronym.
TLC Taiwan Light Source.
TLC TeV Linear Collider.
TLD ThermoLuminescent Dosimeter. Sometimes called a `Film Badge.' Every SLAC employee who has to enter
the area inside the radiation fence must be issued, and carry, a TLD at all times.
TLM TeLeMetry.
TLNG TooLiNG
TLNGB TooLiNG Ball.
TLS ThermoLuminescent Sheet stack (detector). (Japan).
TLV Threshold Limit Value. Maximum workplace, airborne concentrations to which normal, healthy, adult
workers may be exposed daily without adverse effects. Determined by the American Conference of Governmental
Industrial Hygienists. Also see PEL.
TLV-C TLV-Ceiling. An occupational exposure standard which should never be exceeded.
TLV-Ceiling See TLV-C.
TLV-Short Term Exposure Limit See TLV-STEL.
TLV-STEL TLV-Short Term Exposure Limit. An occupational exposure standard which is a 15-minute time-weighted
average which may not be exceeded more than once in a one-hour period and no more than four times in an eight-hour
work shift.
TLV-Time-Weighted Average See TLV-TWA.
TLV-TWA TLV-Time-Weighted Average. An occupational exposure standard which is a time-weighted average for a
normal 8-hour work day and 40-hour work week.
TMA Telescope Mount Assembly (LSST).
TMAE Tetrakis diMethylAmine Ethylene.
T-Matrix A reference to the Twiss Parameters Matrix.
TMIT TransMitted InTensity. A sum signal derived from the 4 striplines of a BPM or from a toroid. The TMIT
signal is a running indication of the beam's transmission intensity down the machine.
TMO Time-resolved Atomic, Molecular and Optical Science end station (LCLS-II)
TMR Tunneling MagnetoResistance
TMS Travel Management System
TMSK Trigger MaSK. A 36 bit mask indicating the allowable broadcast pattern of a beam code.
TMTP Test Move To Production. (OCIO) COMPUTING
TO Technical Operations.
To Be Replaced See TBR.
TOC Technical Operations Committee.
TOC Total Organic Carbon.
TOC Trigger Over Current. A Klystron SDS message.
TOF Time-Of-Flight.
TOFC Trailer On Flat Car.
TOFF Time OFFset.
TOKAMAK Toroidal Magnetic Chamber
TOLS A set of BDES tolerances in the database for trimming and checking a magnet.
TOMCAT Server plugin that creates an environment for servlet execution. (GLAST)
Tone Interrupt Unit See TIU.
Tone Loop A PPS/MPS system circulating AC signals (tone) throughout selected beam monitoring devices
which when interrupted by a fault condition in one of the devices will shut off the machine. It includes a tone
transmitter and a tone receiver (Rx) and does not have to be a closed loop. See TIU.
TOO Target Of Opportunity.
TOP Technical Operations Procedure.
TOP TOP of duct.
TOPAZ TOP And Z. The KEK TRISTAN solenoidal spectrometer with TPC, time projection chamber.
TOPS A network software package used to communicate between Macintosh computers.
TOPZ See TOPAZ.
TORI TORoId.
TORO TOROid. A beam current monitor which uses transformer action to measure the intensity of a beam pulse.
Usually placed around a ceramic gap in the beam pipe.
Toroid See TORO.
Toroid Charge Monitor See TCM.
TORR Named after Torricelli. A unit of pressure equivalent to 1/760 Atmosphere or 133.322 Pascals.
TOTEM an experiment at CERN, called Total Cross Section, Elastic Scattering and Diffraction Dissociation.
Toxic Cloud An airborne mass of gases, vapors, fumes, or aerosols containing toxic materials.
Toxicity The ability of a substance to cause injury once it reaches a susceptible site in or on the body.
TPa TeraPascal. One trillion Pascals.
TPC Total Project Cost.
TPCA Toxic Pits Cleanup Act. (CH&SC Sec. 25122.7, 25208-25208.17)
TPI Tap changer Position Indicator
TPQ Threshold Planning Quantity. (from EPCRA)
TPS Tagged Photon Spectrometer (FNAL)
TPS Taiwan Photon Source.
TPY Tons Per Year.
TQ Technology Quadrupole.
TQFT Topological Quantum Field Theory
TR Travel Office.
TRAC Teachers Research Associate Program.
Track16 Track display program for the 1.6-GeV Magnetic Spectrometer.
Transaction Processing A major type of networked and shared database application where transactions (such as
purchasing an airline ticket) from multiple simultaneous users are immediately recorded in database (or collection
of databases), and where the database remains in a continuous state of updated and current transition. Transaction
processing implies the existence of a robust underlying management system that ensures the integrity of the database
against which the transactions are made, as well as the ability to recover the database to a known point of existence
in the event of hardware or software crash.
Transceiver Transmitter-receiver. The physical device that connects a host interface to a local area network,
such as Ethernet. Ethernet transceivers contain electronics that apply signals to the cable and sense collisions.
Transmission Control Protocol/Internet Protocol See TCP/IP.
Transmitted Intensity See TMIT.
TRANSPORT A computer program for designing and modeling charged particle beam transport systems. It is a first
and second order matrix multiplication program and was developed at SLAC for designing beam line
optical systems.
Transport Layer An OSI layer that is responsible for reliable end-to-end data transfer between systems.
TRAP Penning trap.
TRB Technical design Review Board. (SLAC)
TRC Total Recordable Cases. A rate defined as the number of cases (accidents) per 200,000 person-hours
worked per year.
TRD Transition Radiation Detector
TREF Time REFerence. T-Matrix and beam matrix timing delays associated with each individual PDU. It is the time
difference between a fiducial and a bunch 1 beam BPM signal arriving at that PDU's crate.
TRG TRiGger. A klystron SDS message indicating that there are no triggers present.
TRI Toxic chemical Release Inventory.
Trickle charge Procedure at SSLR where a small amount of beam is injected every few minutes to keep the stored
current steady to within a fraction of a percent.
Trigger See TRG.
Trigger Gate and Synchronization See TGAS.
Trigger Mask See TMSK.
Trigger Multiplexer See TMUX.
Trigger Over Current See TOC.
Trim An operator command to bring a magnet current or a klystron phase to a desired value. If a device has
drifted from its book value, `trimming' it will cause the computer to adjust it back to the proper setting.
Triplet See Final Triplet.
TRIUMF TRIangle University Meson Facility (Canada)
TRMS Ratio of RMS TOLS to TOLS.
TRNARND TuRNARouND.
TRO Travel Reimbursement Office. (SLAC)
Trombone In the positron transport system, just after the positrons are created by the source, the beam line
makes a 180 degree turnaround called `ETA.' The whole assembly, including B1 Bends, a sextupole, and instrumentation,
can physically be moved forward or backward like a trombone slide, causing the path length to vary. This adjusts
the time of arrival of the positrons for re-injection into the LINAC at sector 1.
TRP Thermocouple Reference Plane. A cold junction used as a temperature reference for the 15 thermocouples of a SAM.
TRS Training Registration System.
TRT Total Run Time.
TRT Transition Radiation Tracker
TS Test Stand (Klystron).
TS Time Slot. One of the six zero crossings of the 360 Hz 3 phase PG&E power used to generate timing fiducials.
At a 120pps rep rate, time slots 1 and 4 are used: at 60pps, time slot 1 or 4 is used.
TSA Technical Safety Appraisal.
TSC Terminal Standards Committee.
TSCA hazardous waste and Toxic Substance Control Act. (15 U.S.C. Sec. 2 601 et seq)
TSCD Toxic Substances Control Division. A division of California Department of Health Services.
TSD Treater, Storer, Disposer (ES&H).
TSD Facility See TSDF.
TSDF Treatment, Storage, or Disposal Facility (for hazardous waste). (From RCRA.)
TSI Thermal System Insulation.
TSOM Transmitter Start Of Message.
TSP Total Suspended Particulate.
TSP Titanium Sublimation Pump.
TSP Theory and Special Projects.
TSR Technical Safety Requirements
TSS Total Suspended Solids.
TSSM TeV scale Supersymmetric Standard Model
TT Transverse Tracefill
TTC TESLA Technology Collaboration.
TTE Time Tagged Event
TTF TESLA Test Facility.(DESY)
TTHMs Total TriHaloMethanes.
TTIM A magnet parameter indicating the last time the magnet was successfully trimmed. A magnet database secondary.
TTLC Total Threshold Limit Concentration. (CCR Title 22)
TTO Technology Transfer Office. (SLAC)
TTO Transfer To Operations.
TTS Time-To-Spill
TTU Transportable Treatment Unit.
TUD Tune Up Dump. A safe place to absorb beam energy during tuning and adjustment.
TULIP Trilateration Utility for Locating IP hosts.
TUNE In a storage ring, the fractional part of the quotient when the betatron oscillation frequency (or
synchrotron frequency) is divided into the go-around frequency. The whole digit part of this quotient
is called the betatron number.
Tune To adjust the steering, focus, current or energy of a beam to bring it to proper specifications.
Tune Up Dump See TUD.
Tuple In relational database systems, a record.
TURTLE Trace Unlimited Rays Through Lumped Elements. A computer program used to model beam transport optics by
simulating the propagation of a beam, one particle at a time.
TV TeleVision camera.
TWAS Academy of Sciences for the Developing World. (Known as TWAS for its original name, Third World Academy of Sciences).
TWC Talk, Walk and Clean (Safety Stand-down).
TWG Technical Working Group (2006).
Twiss See TWSP.
Twiss Parameter See TWSP.
Twisted Pair Cable made up of a pair of insulated copper wires wrapped around each other to cancel the
effects of electrical noise.
TWSP TWiSs Parameter. The beam ellipse is given by the matrix: s11 s12 b a = e s21 s22 a g, where
e, b, a, g are the beam parameters: emittance, betafunction, Alpha and gamma respectively. These parameters
have historically been known as the Twiss Parameters after the physicist R.Q. Twiss.
TWT Traveling-Wave Tube.
TWTA Traveling-Wave Tube Amplifiers.
TX Tone Transmitter. See Tone Loop.
TXI Tender X-ray Instrument (LCLS-II)
TXM Transmission X-ray Microscopy.
TXRF Total Reflection X-ray Fluorescence.
Back to top
U Wastes A federal list of non-acute hazardous wastes.
U.S.C. United States Code.
UA1 Underground Area 1. The name of a detector, and the related experiment, at CERN.
UA2 Underground Area 2. The name of an experiment, and the related detector, at CERN.
UA5 UA5 detector at CERN.
UAT User Acceptance Test. (Computing)
U-AVLIS Uranium-Atomic Vapor Laser Isotope Separation (LLNL)
UC UltraCentrifugation.
UCN UltraCold Neutron
UCP Unique Continuation Property.
UCPF Universal Chiral Partition Function
UDP User Datagram Protocol. A transport protocol in the Internet suite of protocols. UDP, like TCP, uses IP
for delivery however, unlike TCP, UDP provides for exchange of datagrams without acknowledgments or guaranteed delivery.
UEC Users Executive Committee.
UED Ultrafast Electron Diffraction.
UEL Upper Explosive Limit or Upper Flammable Limit (UFL). The maximum percentage of a substance in air which
will ignite. See also LEL and Flammability Range.
UEM Ultrafast Electron Microscopy.
UF UltraFiltration.
UFC Uniform Fire Code.
UFC UltraFast science Center. (Stanford)
UFL See UEL.
UFVA Unclassified Foreign Visits and Assignments. (DOE)
UGC Uppsala General Catalogue of Galaxies.
UGPS University Grant Program Subpanel.(DOE and NSF)
UH Undulator Hall (LCLS).
UHE Ultra High Energy.
UHECR Ultra High-Energy Cosmic Rays.
UHF Ultra High Frequency. Allocated band of radio frequencies from 300 Megahertz (MHz) to 3,000 MHz.
UHV Ultra High Vacuum. The vacuum condition below about 10 exp (-6) TORR. Storage rings operate two to
four orders of magnitude under UHV.
UI User Interface.
UIC Underground Injection Control. (from SDWA)
UIMS User Interface Management System. UIMSes are high-level GUI building tools. On the same underlying data, you
can relatively easily create different types of user interfaces. UIMSes are also called GUI builders.
UKQCD United Kingdom Quantum Dynamics Collaboration.
UL Underwriters Laboratory.
Ultra High Frequency See UHF.
Ultra High Vacuum See UHV.
ULXs Ultra-Luminous compact X-ray sources.
UML Unified Modeling Language.
UN/NA United Nations/North American hazardous materials code.
UND UNDulator.
UND UNDer
Underground Area 1 See UA1.
Underground Area 2 See UA2.
Undulator A permanent magnet, used like a wiggler, to generate more synchrotron light by causing the beam to
bend rapidly back and forth.
UNESCO United Nations Educational, Scientific, and Cultural Organization.
Uninterruptible Power Supply See UPS.
Universities Research Association See URA.
UNIX A computer operating system developed by AT&T. It is available on a wide variety of computing platforms.
It is noted for its portability and interactive software tools.
Unix to Unix Copy Program See UUCP.
UNP Unbounded Nano Particle.
Unsaturated Zone A subsurface zone containing water under pressure less than that of the atmosphere,
including water held by capillarity, and containing airs or gases generally under atmospheric pressure.
It is limited above by the land surface and below by the water table. Synonym: Vadose Zone.
UO Users Organization.
UOEC Users Organization Executive Committee.
UOR Unusual Occurrence Report.
UPK User Productivity Kit. (PeopleSoft).
Upper Explosive Limit See UEL.
Upper Flammable Limit See UEL.
UPS Uninterruptible Power Supply. An emergency power supply used in PPS systems where power must not be
interrupted for safety reasons. Consists of a large bank of batteries and control circuitry.
UPSTR UPSTReam
URA User Research Administration (SSRL, LCLS)
URA Universities Research Association. The governing body for Fermilab and the former SSC.
URI Uniform Resource Identifier. The generic term for all types of names and addresses that refer to objects
on the World Wide Web. A URL is one kind of URI.
URL Uniform Resource Locator. Standardized formatted entities within hyper-text documents which specify a
network service or document to establish a link.
URM Under Represented Minorities
URQMD UltraRelativistic Quantum Molecular Dynamic.
USA Unconventional Stellar Aspect satellite experiment.(Group K)
USAXS Ultra Small-Angle X-ray Scattering.
USC Ultrafast Science Center (SLAC)
USCG United States Coast Guard.
USDA United States Department of Agriculture.
USDW Underground Source of Drinking Water.
USGBC U.S. Green Building Council.
USGS United States Geological Survey.
USI Unreviewed Safety Issue.
USLCSG United States Linear Collider Steering Group.
USN United States Navy.
USPAS United States Particle Accelerator School. A twice-yearly school that rotates among research universities
throughout the U.S. and draws faculty from a variety of institutions to teach intensive courses on beam science
and technology.
USPHS United States Public Health Service.
USR Ultimate Storage Ring.(proposed) A light source designed to produce brighter X-ray beams than the current
synchrotrons can offer.
USSKA United States Square Kilometer Array Consortium.
UST Underground Storage Tank.
USTC University of Science and Technology of China.
USW United Stanford Workers.
UT Upper Transformer
Utah Steel 460 tons of mild steel was obtained by SLAC from the University of Utah Neutrino Facility in 1975
that was subsequently used to fabricate a large number of magnets at SLAC for SLC, PEP and LCLS
UTEP University of Texas at El Paso. (SSRL Gateway Partner)
UTIC Universal Time Interval Counter.
UTR University Technical Representative.
UTS Ultramedia Tools Series. OS/2, Windows, and DOS multimedia software products for authoring, graphics,
audio, animation, and video that share common file formats and a similar user interface.
UUCP Unix to Unix Copy Protocol. A protocol used for copying files between consenting UNIX systems, and
for handling e-mail. Mostly superseded, but still used in low budget situations.
UV UltraViolet
UX User eXperience.
UXSS Ultrafast X-ray Summer Seminar
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V.32, V.32bis, V.42, V.42bis CCITT-based standards for modem communication. V.32 covers speeds up to
9,600 bps. V.32bis covers modem communication at speeds up to 14,400 bps. V.42 covers error correction by
V.32-compliant modems. V.42bis covers data compression by V.32-compliant modems.
VAC VACuum Group.
VAC Volts Alternation Current
VACG VACuum Gauge.
VACT Value ACTual. Equivalent to BACT for devices other than magnets that use DAC / SAM control and read-back.
Vadose Zone See Unsaturated Zone.
Value Actual See VACT.
VAP Vendor-Acquired Property.
VAP Vector Axial-vector Pseudoscalar
Vapor A gaseous form of a liquid or a solid, such as water vapor.
Vapor Density The ratio of the density of a vapor to the density of air.
Vapor Pressure The pressure exerted by a vapor against the sides of a closed container. It is temperature
dependent.
VAR Voltage Amp Reactive
Variable Voltage Substation See VVS.
Variance Government permission for a delay or exception in the application of a given law, ordinance,
or regulation.
VATLY Vietnam Auger Training LaboratorY.
VATValve A type of vacuum valve. VAT is the brand name of this fully closing valve. Vat valves are also
called `Slow Valves.'
VB Vertical Bend.
VBF Vector Boson Fusion.
VC Vertex Chamber.
VCO Voltage Controlled Oscillator.
VCS Virtual Compton Scattering
VD Volume Damper
VDC Volts Direct Current
VDI Voluntary Disability Insurance.
VDU Vernier Delay Unit. Allows 0-10 nsec of time delay for a NIM trigger.
VE Value Engineering.
VEC Volitional Engineering Controls. (ES&H)
VECC Variable Energy Cyclotron Centre (Calcutta)
VEF Vietnam Education Foundation. (US)
VELO VErtex LOcator. (LHCb)
VEP Violations of the Equivalence Principle
VEPP See NOVO VEPP
VERITAS Very Energetic Radiation Imaging Telescope Array. Cherenkov telescope at the Fred Lawrence Whipple Observatory (FLWO)
in southern Arizona, USA.
Vernier Delay Unit See VDU.
Versaterm A file transfer and communication protocol for using a MAC or a PC as a terminal. Versaterm is a
commercial communication program for interfacing PCs to mainframes.
Very High Frequency See VHF.
VES Vertex Spectrometer Facility at 70 GeV IHEP accelerator.
VETO A CAMAC module that receives fault information and sends it to micros in order to flag corrupted data to BPMPs or
other detectors. The klystron veto system provides a fast signal to all micros that a klystron has missed firing on a
beam pulse. Originally designed to gate the experimenter's detection equipment off on pulses that are of the wrong energy
due to a misfiring klystron.
VGC Vacuum Gauge Controller. Monitors vacuum at every klystron/ modulator. Interrupts trigger to modulator when klystron
vacuum is bad.
VHAP Volatile Hazardous Air Pollutant.
VHC Vaden Health Center. (Stanford)
VHDL VHSIC Hardware Description Language.
VHE Very High-Energy
VHF Very High Frequency. Allocated band of radio frequencies from 30 Megahertz (MHz) to 300 MHz.
VHRA Very High Radiation Area.
VHSIC Very High Speed Integrated Circuit.
Vi Visual Interface. Developed by Bill Joy, Vi became the de facto standard UNIX editor until the rise of EMACS
after 1984. It is still widely used.
Video Digitizer Clock Interface See VDCI.
Video Distribution System See VDST.
VIDMAN Virtuelle Institut für Dunkle Materie und Neutrinophysik. (dark matter and neutrino physics)
VIKHOS Virtuelles Institut für Hochenergiestrahlungen aus dem KOSmos. (high-energy radiation from the cosmos)
VIPAC Virtual Institute for PArticle Cosmology.
VIPER VIsualization for PingER.
VIRGO a Michelson laser interferometer.
Virtual Memory System See VMS.
VIRUS Visible Integral-field Replicable Unit Spectrograph.
Virus A program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes.
Most viruses can also replicate themselves. All computer viruses are manmade. A simple virus that can make a copy of itself
over and over again is relatively easy to produce. Even such a simple virus is dangerous because it will quickly use all
available memory and bring the system to a halt. An even more dangerous type of virus is one capable of transmitting
itself across networks and bypassing security systems.
VISA Visible to Infrared SASE Amplifier.
VISAR Velocity Interferometer System for Any Reflector (LCLS)
VIWG Vertical Integration Working Group (ES&H).
VLA Very Large Array.
VLAM Vertical LAMbertson. See Septum.
VLBA Very Long Baseline Antenna (Arizona).
VLF Very Low Frequency
VLHC Very Large Hadron Collider. A facility, now in the planning stages, to collide beams of protons and antiprotons
with energies of 50 - 100 TeV per beam.
VLI Violations of Lorentz Invariance
VLK Very Large Key (LCLS).
VLM Very Low Mass
VLPC Visible Light Photon Counter
VLQ Very Low Q**2.
VLSI Very Large-Scale Integration.
VLSP Virtual Lightest Supersymmetric Particle
VLT Very Large Telescope. (Chile)
VLT Valiant Little Terminal. A terminal emulation program for the Amiga.
VLT Visible Light Transmission. The amount of visible light passing through a filter, weighted for the response
of the human eye, expressed as a percentage.
VM Virtual Memory.
VMD Vector Meson Dominance
VMDD Vacuum microwave Devices Department. (SLAC)
VME Versa Module Eurocard. A computer architecture. The VMEbus is a standard of industry used in data acquisition
in detectors (BaBar) and controls for the accelerator (feedback system)
VMI Velocity Map Imaging spectrometer.
VMO Very Massive Objects
VO Vacuum oscillations
VOC Volatile Organic Compounds.
VoIP Voice over Internet Protocol
Volatilization Vaporizing or evaporating quickly. Volatilization rate is a function of turbulence, temperature, and
vapor pressure of the liquid.
VPN Virtual Private Network
VPP-ISMS Voluntary Protection Program - Integrated Safety Management System .
VRO Vera Rubin Observatory (LSST)
VRVS Virtual Room Videoconferencing System.
VSE Vision for Space Exploration. (NASA)
VSED Vacuum Science and Engineering Department.
VSFT Vacuum String Field Theory.
VT Video Terminal. See VDT.
VT100 A type of computer terminal made by Digital Equipment Corporation. Many terminals emulate VT100 to be
compatible with servers and software. Macs and PCs can also emulate VT100.
VTK Visualization Tool Kit.
VTO Variable Tap-Off
VTR Vent Thru Roof
VUE Visitor, User and Employee center. (SLAC)
VUV Vacuum UltraViolet.
VVDZ Van Dam-Veltman-Zakharov.
VVS Variable Voltage Substation. The AC power supplies for the klystron modulators in the LINAC. Each VVS feeds
two sectors of the LINAC. They are remotely controlled to provide from three to six hundred volts to the modulator
power supplies. Also called Variable Voltage Sources.
VXD VerteX Detector
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W Watt.
W Wall (abbreviation used in SLAC drawings)
W3 See WWW.
W3C World Wide Web Consortium. An international consortium of organizations involved with the Internet and the
Web. W3C's purpose is to develop open standards so that the Web evolves in a single direction.
WA Work Authorization.
WAA Waste Accumulation Area.
WAC Waste Acceptance Criteria.
WAH Word-Aligned Hybrid, a type of compression method.
Wakefield The field created by a bunch of charged particles as it passes through a beam pipe. The charges
induced in the wall of a beam pipe by the leading edge of the bunch have an effect (usually bad) on the tail
of the bunch. If the beam is centered, wakefields will cancel each other by symmetry, but if the beam is
closer to one wall, the tail will be attracted to this wall resulting in a `banana' shaped bunch
(Transverse Wakefield). A wakefield also can be created in RF cavities by the loading effect: the tail
gets less energy than the head of the bunch (Longitudinal Wakefield). The deceleration on parts of the
bunch caused by wakefields can be up to 2 GeV.
WALTA Washington Large-scale Time-coincidence Array.
WAMC Wrap-Around Mode Converter.
WAN Wide Area Networking.
WAPA Western Area Power Administration.
Warm Ion Calorimeter See WIC.
Warning Property A sign, such as odor, taste, or irritation, that a respirator is beginning to
lose its effectiveness.
WaRP WIMP Argonne Programme.
Warp LBNL accelerator simulation code.
WarpX LBNL accelerator simulation code combined with the BoxLib high-resolution refinement tool to create a new
code for future exascale computing architectures.
WAS Work AuthorizationS
WASM A simple standalone x86 assembler, originally shipped with Version 10.0 of Watcom C/C++.
Water Table The surface of an unconfined aquifer at which the pressure is atmospheric. It is the level at which
water stands in wells that penetrate the uppermost part of an aquifer.
WAX Wide-Angle Xray.
WB WeBer unit
WBS Work Breakdown Structure.
WBT Web-Based Training.
WCLG Water CooLinG
WD White Dwarf.
WDR Waste Discharge Requirements. (issued by RWQCB)
WDTS Workforce Development for Teachers & Scientists (DOE)
WDVV Witten-Dijkgraaf-Verlinde-Verlinde
Web Page An HTML file viewable on the World Wide Web. Associated with the page itself, there may be other
kinds of Web files like Postscript , PDF, image, movie, and sound files.
Web Server A computer that delivers (serves up) Web pages. Every Web server has an IP address and possibly
a domain name. For example, if you enter the URLhttp://www.slac.stanford.edu/detailed.html in your browser, this
sends a request to the server whose domain name is slac.stanford.edu. The server then fetches the page named
detailed.html and sends it to your browser.
WEFTEC Water Environment Federation's annual Technical Exhibition and Conference.
West Turn Around See WTA.
WET Whole-Earth Telescope.
WET Waste Extraction Test. (CCR Title 22)
WFIRST Wide-Field Infrared Survey Telescope.
WFO Work For Others.
WFO Wave Function Origin
WFPC2 Wide Field and Planetary Camera 2
WG Working Group.
WG1 A klystron summary display message indicating that there is a problem with the waveguide water cooling
system (flow switch #1).
WGV A klystron SDS message indicating that there is waveguide vacuum fault.
WHA tungsten heavy alloy
WHDL Watt-Hour Demand Limiter
WHIM Warm-Hot Intergalactic Medium.
WHONDRS Worldwide Hydrobiogeochemistry Observation Network for Dynamic River Systems (DOE)
Wiggler A type of bend magnet designed for the purpose of creating synchrotron radiation by `wiggling'
the beam rapidly to and fro. See Undulator.
WIMP Weakly Interacting Massive Particle.
WIP Work Integration Plan. Used to document the coordination of red work. (SLAC ES&H)
WIPP Waste Isolation Pilot Plant (Carlsbad, NM).
WIRE Wide-field InfraRed Explorer.
WIRE Wire chamber.
Wire Scanner Wire scanners are beam profile monitors used to provide accurate measurements of beam size
and position in all three planes (vertical, horizontal and longitudinal) for beam feedback systems and beam
optimization procedures. Components include wires capable of being moved precisely through the path of a beam,
and a detector which can accurately measure the amount of charge striking a wire. When in use, a wire is
scanned across the path of a beam, and a plot of wire position versus beam intensity is generated that represents
the beam profile. Wire scanners are used to measure the emittance of the beam.
WIRED World-wide-web Interactive Remote Event Display. A general purpose particle physics event display program
developed by Mark Donszelmann of CERN.
WISE Wide-field Infrared Survey Explorer. (NASA)
WISP Weakly Interacting Suv-eV Particle.
WKB Wentzel-Kramers-Brillouin (a method of calculating wave functions)
WKL A klystron summary display message indicating that there is a problem with the klystron water system.
WL Working Level. A unit of measure for documenting exposure to radon decay products. One working level
is equal to approximately 200 picocuries per liter.
WLCG Worldwide Lhc Computing Grid.
WLD Water LoaD
WLDMT WeLDMenT
WLM Working Level Month. A unit of measure used to determine cumulative exposure to radon.
WM Waste Management / Minimization. (ES&H)
WMAC Wrap-around Mode Converter
WMAP Wilkinson Microwave Anisotropy Probe.
WONDER Workshop On Next Dark-matter Experimental Research.
Working Level See WL.
Working Level Month See WLM.
Workstation A networked computer which typically has more power than a PC or Macintosh, but less power
than a minicomputer.
WORM Write Once, Read Many.
Worm A computer program which replicates itself. The Internet Worm was perhaps the most famous. It successfully
(and accidentally) duplicated itself on systems across the Internet.
WP Work Package.
WPAC Work Planning And Control.
WPC Work Planning and Control (Also shown as WP&C)
WPI World Premier International research center initiative. (Japan)
WS Wire Scanner.
WSBK W-Band Sheet Beam Klystron.
WSCNR Wire SCaNneR.
WSF A klystron summary display message indicating that the water summary has a fault.
WSP Work-Study Program.
W/SR Watt per SteRadian
WSRF Web Service Resource Framework from OASIS.
WSS Work Smart Standards.
WTA West Turn Around. A reference to that part of the positron beam transport line that makes a 180 degree turn
and returns to sector 1.
WUS Workshop on Undulator Systems (for Free Electron Lasers).
WWS WorldWide Study (of physics and detectors for the ILC).
WWSOC WorldWide Study Organising Committee (ILC).
WWTP Waste Water Treatment Plant.
WWW World-Wide-Web. The leading information retrieval service of the Internet (the worldwide computer network).
The Web gives users access to a vast array of documents that are connected teach other by means of hypertext or
hypermedia. Developed by Tim Berners-Lee and his colleagues at CERN in 1990.
WYSIWYG "What You See Is What You Get." Used to describe word processors and editors which allow you to edit an
exact facsimile of what will be printed, including equations, figures, etc."
WZ Wess-Zumino
WZNW Wess-Zumino-Novikov-Witten
WZW Wess-Zumino-Witten
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X cross.
X Corrector See XCOR.
X Recommendations The CCITT documents that describe data communication network standards. Well-known
ones include: X.25 Packet Switching standard, X.400 Message Handling System, and X.500 Directory Services.
X Window System (TM) A popular window system developed by MIT and implemented on a number of workstations.
X/Open A group of computer manufacturers that promotes the development of portable applications based on UNIX.
They publish a document called the X/Open Portability Guide.
XAFS X-ray Absorption Fine Structure.
XANES X-ray Absorption Near Edge Structures.
XAS X-Ray Absorption Spectroscopy.
XBBM X Length Bunch Monitor.
XCOR X CORrector. A small dipole magnet acting in the horizontal plane. Sometimes anXCOR is a trim
winding on a larger bend magnet.
X-COW Two work stations used as a COW. One of the stations is used for display only, the other for a
cursor selectable menu (uses DECXWINDOW).
XCS X-ray Correlation Spectroscopy (LCLS).
XENIX A version of UNIX originally from Microsoft, now from SCO (Santa Cruz Organization).
XENON Experiment proposed in 2002 using the dual phase type projection chamber approach to detect
WIMP dark matter directly.
XES eXperimental End Stations. (LCLS)
XES X-ray Experimental Systems. (LCLS)
XFD eXperimental Facilities Division (LCLS).
XFDSO eXperimental Facilities Division Safety Office (LCLS).
XFEL X-ray Free Electron Laser.
XFELO XFEL Oscillator
XFO X-ray Facilities Operations. (SLAC)
XIP X-ray Improvement Project. (LCLS)
XKMS XML Key Management System.
XLAM X-ray Laboratory for Advanced Materials. Name changed to SIMES in 2008.
XLDB eXtremely Large Databases (workshop).
XLEAP X-ray Laser-Enhanced Attosecond Pulse
XM-2 SoftX-ray microscopy facility (ALS).
XMASS Cold dark matter search using liquid Xenon (Kamioko Observatory)
XMC X-ray Monte Carlo.
XML eXtensible Markup Language. A pared-down version of SGML, designed especially for Web documents.
It enables designers to create their own customized tags to provide functionality not available with HTML.
For example,XML supports links that point to multiple documents, as opposed to HTML links, which can
reference just one destination each.
XMM-N X-ray Multi-Mirror Mission - Newton. Launched by an Ariane 504 on December 10, 1999. (ESA)
Xmosaic AnX11/Motif WWW browser developed by National Center for Supercomputing Applications (NCSA).
XPCS X-ray Photon Correlation Spectroscopy
XPD X-ray Powder Diffraction.
XPEEM X-ray PhotoEmission Electron Microscopy.
XPP X-ray Pump Probe (LCLS).
XPS X-ray Photoelectron Spectroscopy
XPSCL X-ray Phase Safety Checklist. (LCLS)
XPUS Interchangeable Processing Units.
XRAFEL X-ray Regenerative Amplifier Free Electron Laser
XRB X-Ray Background
XRD X-Ray Diffraction.
XRD-F X-Ray Diffraction and Fluorescence facility. (SSRL)
XRF X-Ray Fluorescence. Biological rapid scanning imaging technique.
XROOTD A highly scalable architecture for data access.
XRT X-Ray Telescope.
XRT X-Ray Tunnel (LCLS)
XSPRT cross SuPpoRT.
XSS cross-Site Scripting. (Computing)
XT X Toolkit Intrinsics. A C library to create and use interface components called widgets to build GUIs.
Pre-built collections of widgets are available like the Motif widget set.XT provides a higher level of screen
and input manipulation than theXlib C library.
XTC eXtended Tag Container.
XTCAV X-band radio frequency deflector.
XTES X-ray Transport and Experimental Systems, also known as FEE (Front -End Enclosure)
XTH X-ray Transport Hall. (LCLS)
XTOD X-ray beam Transport, Optics and Diagnostics.
XUV eXtreme-UltraViolet
X-Windows A standard protocol for computer display windows and graphics developed by MIT and available
for most computers. DECWINDOW is the version for VAXes and microvaxes, MACX is the version for MACs.
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Y Corrector See YCOR.
YAG laser neodymium-doped Yttrium Aluminum Garnet Nd:Y3Al5O12.
YBCO Yttrium Barium Copper Oxide
YCOR Y CORrector. A dipole magnet acting on the vertical position and angle of a particle.
YFS Yennie-Frautschi-Suura
YITP C N Yang Institute for Theoretical Physics (Stony Brook University )
YM Yang-Mills
YN hYperon-Nucleon
YOP Youth Opportunity Program.
YP Yellow Pages. See NIS.
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Z A fundamental particle with the same quantum numbers as the photon, but with a mass of 91.16 GeV. Like
the W- and W+ particles, the Z is a carrier of the electroweak force. Discovered at CERN in 1983, the production
and study of this neutral intermediate boson is the object of the SLC.
ZDR Zeroth-Order Design Report (NLC).
ZEPLIN ZonEd Proportional scintillation in Liquid Noble gases. (UK)
Zeta The Greek letter (Z) used for the chromatic aberration function.
Zevatron Hypothetical, highly exotic source capable of accelerating particles to 1 ZeV.
ZTA Zero Trust Architecture
ZWP Zero Waste Program.
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