- Usually refers to a beam dump. ALSO: D.
- Dipole magnet.
- D Wastes
- A federal waste category for those wastes which exceed
maximum concentrations of toxic components based on the EP
- 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.
- Data Assembly Building. Now called the Main Control Center
- Digital to Analog Converter. Usually used to control a power
- Director's Advisory Committee.
- Director's Assurance Council. (SLAC, 2011- )
- DAC versus Current Goodness
- See DVIG.
- CAMAC DAC location. A magnet database secondary.
- Direct ACTion.
- A magnet database secondary indicating the last DAC value.
- To run down a magnet to zero current. This is done by
putting zero volts on the DAC that controls the magnet's power
- A server or process running on a server that lies dormant
until called upon to perform a service. Most servers are daemons.
- phi-meson factory at the Frascati National Laboratories
- Dump All Low Extracted Currents. A system which senses
current in the Damping Ring before extraction and stops extracted
beam in the Beam Switch Yard if current is below a specified
- particle DArk MAtter search. (INFN)
- particle DArk MAtter search using Large sodium Iodide Bulk
for RAr e processes.
- 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
- Damping Ring Injection Point
- See DRIP.
- Damping Ring Phase Processor
- See DROPP.
- Damping Ring RF
- See DRRF.
- Damping Ring Turns Counter
- See DRTC.
- see DAFNE.
- 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.
- Defense Advanced Research Projects Agency.
- Days Away, Restricted, or Transferred. A subset of the Total
Recordable Case (TRC) rate.
- Data Acquisition System (SLD)
- Degree Angular Scale Interferometer.
- DESY double-arm spectrometer.
- An abbreviation for DATA used in VAX file terminology as in
- 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.
- 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
- 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.
- Service mark of the American Telephone and Telegraph Company
for various hardware products.
- See AOPDF entry.
- Database. A collection of information organized in such a
way that a computer program can quickly select desired pieces of
- Deuterium bubble chamber.
- Detailed Baseline Design. (ILC)
- DataBase EXecutive. A VAX process which transfers data
between the micros and the host computer.
- DataBase GENeration. The process of rebuilding the database
on the SLC VAX. It is a process that adds new signals to the
database and simultaneously checks that no two signals have the
- Transfer of the complete database from the SLC VAX to the
MCC VAX (or vice versa). It involves a brief shut down of
operations. (The computer can't use the database while it is
- Determined By Management.
- Data Challenges (GLAST simulations).
- Data Center.
- Drift Chamber.
- Defense Contract Audit Agency.
- Design Cost Board. (ILC)
- Drift Chamber Beta-Ray Analyzer
- DC Bending Dipole.
- Disoriented Chiral Condensate
- Directorate Conference Coordinator.
- Direct Current Current Transformer. A system used in storage
rings to measure the stored current. It uses a toroid and an
- 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).
- Drift CHamber. (BaBar)
- Dispositif de Collision dans l'Igloo. The electron -
positron storage ring at ORSAY.
- Digital Command Language. The command language used by the
- Document Change Order
- Detector Concepts Report. (ILC)
- Distributed Control System.
- Drift Chamber Vertex Detector. It is used for high-precision
tracking of charged particles near the interaction point.
- Data Challenge 1. (GLAST)
- DC1 included analysis of data sets representing one day's
worth of data. (See Data Challenge 1 Closeout Meeting.)
Glast Category: operations
- Data Challenge 2. (GLAST)
- DC2 included extensive analysis of 55 days of simulated data
which, relative to DC1, was more realistic in terms of increased
detail and improvements of the detector simulation, event
classification, and the sky. (See Data C hallenge II web pages.)
Glast Category: operations
- Decade of Discovery in Astronomy and Astrophysics.
- Digital Down Converter.
- A device which measures and reads out the rate of change of
the DCCT. It is used to find the fill/loss rate of current in
- 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.
- Damped Detuned Structure
- Dark Energy.
- Dead Time
- Time during which the LAT does not trigger in response to
Gamma-ray events due to physical limitations on the readout rate
of the front-end and data acquisition electronics.
Glast Category: general
- Department of Energy Acquisition Regulations.
- Experiment conducted at the Frascati National Laboratories
(Italy) phi-meson factory DAFNE
- Dark Energy survey Camera. (Chile-2012)
- Removal of chlorine from a substance by chemically replacing
it with hydrogen or hydroxide ions in order to detoxify the
- A VAX communications system protocol between DEC computers.
Decnet provides remote file service and remote terminal sessions.
It can be used on the Ethernet cable system.
- 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
- 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.
- The process by which a chemical is reduced to a less complex
- Deep Imaging Multi-Object Spectrograph.
- Draft Environmental Impact Statement.
- Direct ELectron COunter, an experiment at PEP.
- 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.
- The use of the petition process to have a facility's toxic
- DEtector with Lepton Photon and Hadron Identification.
- DEMOnstration power plant (ITER).
- A Monte Carlo program for electron-down quark (e-d)
- DEep Near Infrared Survey of the southern sky
- Mass per unit of volume, commonly expressed in grams per
cubic centimeter (g/cc). The density of water is 1.00 g/cc.
- Director of Emergency Operations.
- Deputy Engineering Operator In Charge.
- DEpleted P-channelField Effect Transistor detector.
- DEpleted P-channel Field Effect Transistor. Pixel detector
develop ed at MPI Halbeiterlabor Munchen.
- Dark Energy Survey.
- 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.
- Dark Energy Space Telescope
- Deutsches Elektronen-SYnchrotron (Hamburg, Germany)
- DESY HERA
- DESY Hadron Electron Ring Accelerator
- DESY PETRA
- DESY Positronen Elektronen Tandem Ring Accelerator (1978-
1986), now PETRA II.
- Dark Energy Task Force. (HEPAP)
- Department of Food and Agriculture. (California)
- Deutsche ForschungsGemeinschaft. (German Research
- |Ground software package that provides a user interface to
the science data transmitted by the onboard FSW. DFI presents an
abstract representation of the datagrams inside the science data
stream, allowing user code to access th|
|e contents of those datagrams without knowledge of their
physical structure. DFI itself uses interfaces provided by the
QSEP, QSEC, and other Q-packages in the FSW repository.|
Glast Category: data processing, package, software
- 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.
- Density Functional Theory.
- Display GRouP. A VAX primary.
- Discharge to Ground Water.
- Department Head.
- Digital Hadron Calorimeter. (ILC)
- Dynamic Host Configuration Protocol. An Internet protocol
for automating the configuration of computers that use TCP/IP.
- Drell Hearn Gerasimov Iddings sum rule
- Department of Health and Human Services. (federal)
- Department of Health Services (California, aka CDHS, SDOHS,
- Third-generation synchrotron radiation source under
consideration for construction in the UK.
- DIagram ANAlyser
- Deep Inelastic Collisions
- Digital Input Device label defiNitions. A VAX primary.
- Differential Pumping Station
- See DPS.
- elastic-like scattering
- Tool for fast parametric simulations of detector phenomena.
- 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.
- Digital Command Language
- See DCL.
- Digital Input Device Label Definitions
- See DIDN.
- Digital to Analog Converter
- See DAC.
- Any analog to digital converter. See also ADC.
- A device used to digitize the light intensity created when a
profile monitor is inserted in a beam transport line.
- A computer program used to study particle behavior in
circular machines and in beam lines
- 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
- 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.'
- A magnet with a North and South pole, typically used to bend
or steer a beam.
- Department of Industrial Relations. (California)
- Detector of Internally Reflected Cherenkov light. DIRC is a
device developed for use in the SLAC BaBar Detector. Also:
Detection of I nternally Reflected Cerenkov Light. Invented by
- Direct Current Current Transformer
- See DCCT.
- Directory Services
- A network function providing resource (file, user, printer,
applications) information to end users.
- Dust InfraRed Toolbox.
- Deep Inelastic Scattering
- Converting a binary program into human-readable machine
- Disaster Monitor
- Obsolete. See Burn Through Monitor.
- Disc Loaded WaveGuide
- See DLWG.
- 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.
- Display Group
- See DGRP.
- 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 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
- 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.
- A test designed to demonstrate a fully functional
observatory in which the LAT is operated exactly as it will be on
orbit. During a DITL, the LAT is under the control of commands
stored on the observatory and executed in an ab
solute time sequence. DITLs include a number of SAA passes
and physics run starts/stops. Tests also exercise the full range
of observation modes by including LAT-initiated Autonomous
Repoint Requests and Target of Opportunity pointings.
Glast Category: general, operations
- The increase in the diameter of a beam as a function of z
- Divide By Four
- Any circuit which divides a frequency (or other parameter)
- Divide By Four
- A module which divides by four the S-BAND frequency to get
the RF subharmonic used in the damping rings.
- Deutsches KresForschungsZentrum, a German cancer research
- Dispersionless Kadomtsev-Petviashvili.
- Dog-Leg beam position monitor. (LCLS)
- Double Logarithmic Approximation
- Direct or Delectric Laser Acceleration.
- DELCO detector at SLAC-SPEAR or SLAC-PEP.
- Discretized Light Cone Quantization
- Delay Line Distribution System.
- Double energy Large Hadron Collider.
- Double Leading Logarithmic Approximation
- Data Loss Prevention. (Symantec)
- DELPHI detector at LEP.
- Deputy Laser Saftey Officer.
- Disc Loaded Wave Guide. The LINAC accelerator pipe is a Disc
Loaded Wave Guide.
- Deferred Maintenance.
- Disaster Monitor. See Burn Through Monitor.
- Direct Memory Access.
- Data Management Plan.
- Discharge Monitoring Report (from CWA).
- Differential Microwave Radiometers
- see CDMS.
- Dark Matter Scientific Assessment Group.
- Dust Mask User's Form.
- Data Management Working Group (SD&H).
- Magnetic detector no. 1 at Orsay DCI collider.
- Magnetic detector no. 2 at Orsay DCI collider.
- Disjunctive Normal Form
- Discrete NonLinear Schrodinger
- Domain Name System. The method used to convert Internet
names to their corresponding Internet numbers.
- DowN STReam.
- Director's Office.
- Dissolved Oxygen.
- Department Of Defense. (federal)
- A twelve-pole magnet.
- Department Of Energy. Supercedes ERDA and the AEC.
Established 4 August 1977.
- DOE ACTS
- Department of Energy Academies Creating Teacher Scientists.
- DOE ER
- Department of Energy, Energy Research. This department
supersedes the Energy Research and Development Agency (ERDA),
which superseded the Atomic Energy Commission (AEC).
- DOE HQ
- DOE HeadQuarters (Washington, DC).
- DOE OBER
- Department of Energy Office of Biological and Environmental
- DOE SF
- DOE San Francisco Field Office.
- Department of Energy Oakland Operations Office
- Department of Energy Oak Ridge Operations office.
- DOE Laboratory Accreditation Program.
- Department of Energy Nationwide Telecommunication Services.
- Department of Health Services (California, aka CDHS, DHS,
- Digital Object Identifier.
- Digital Optical Modules
- 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.
- Direct Observation of the NU Tau. Experiment (FermiLab) that
in 2000 directly observed the tau neutrino for the first time.
- DOppel RIng Speicher, a storage ring at DESY.
- 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
- An instrument to measure integrated radiation dose. See also
- 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: 188.8.131.52.
- Dotted Quad
- A set of four numbers connected with periods that make up an
Internet address, for example: 184.108.40.206.
- Deputy Physics Analysis Coordinator (BaBar).
- Division of Particles and Beams (American Physicsl Society).
- Diffractive Parton Distribution Functions.
- Division of Particles and Fields (American Physical Society)
- Data Preservation and Long-Term Analysis. (HEP)
- Differential Pumping Station. A refrigerated section of
waveguide which is used to maintain a difference in vacuum
pressure between the LINAC and BSY, yet allows beam to pass (also
called Refrigerated Baffle).
- Energy-Dependent Partial-Wave Analysis.
- Dynamic Quantum Clustering.
- Damping Ring.
- Disaster Recovery.
- Destruction and Removal Efficiency.
- Dosimetry and Radiological Environmental Protection.
- 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.
- Drift Chamber Vertex Detector
- See DCVD.
- Damping Ring Injection Point. 1. A PPS area between PPS
Sector 0 and PPS Sector 2, and the Damping Ring vaults. 2. The
point where the beamlines from and to the rings are connected
(the Ten Finger Box).
- Damping Ring Interaction Point.
- A software module that controls an input/output port or
external device. PC/TCP uses a device driver to control the
- See DRPP
- Dropp Phase
- A Damping ring phase shifter used in phase ramping the
damping ring RF to phase the beam with respect to the LINAC S-
- Damping Ring Phase Processor. A CAMAC module driving the
Damping Ring Phase Shifter. (Sometimes appears as DROPP.)
- Damping Ring RF. A VAX primary.
- Damping Ring Turns Counter. A CAMAC module including a 20
bit counter reset by the FIDO missing pulse and incremented by
the MTG: used to synchronize extraction from the damping rings
with respect to PEP RF when filling the PEP storage ring.
- Damping Ring Vault. (SLC)
- Direct Supervisor.
- Desktop Support.
- Dyson-Schwinger equations
- Dyson-Schwinger Equation Studies.
- Digital Signal Processors
- dwarf Spheroidal (galaxies).
- Data Set Ready.
- Doubly Special Relativity.
- Decision Support Services.
- Daylight-Savings Time.
- Data Summary Tapes.
- Discharge to Surface Water.
- Dynamically Triangulated
- Drift Tube.
- Drift-Tube Chambers.
- Document Type Definition (as for SGML)
- Data Terminal Equipment.
- Data Transfer Module.
- Data Terminal Ready.
- Domestic Treatment Works.
- Deep Underground Detector (IMB).
- Deep Underwater Muon And Neutrino Detector.
- A device to absorb the full power of a beam, either while
tuning or after it has been used by an experiment.
- Device Using Pulse Control Devices.
- Deep Underground Science and Engineering Laboratory (at
Homestake Mine, South Dakota).
- 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.
- Deeply Virtual Compton Scattering
- The product of the DAC and power supply transfer functions.
For conversion of DAC units to power supply output units. A SLC
VAX database secondary.
- A common abbreviation for DeVice Independent. It refers to
output produced by TeX, and is often used as the "extension"
portion of a computer file specification containing TeX output,
as in "myletter.dvi".
- DAC Versus current Goodness. The root mean square residual
error (in DAC bits) from the linear fit as determined from a
calibration. A magnet database secondary. Also, a SLC VAX
- A commonly-used program that convertls TeX DVI files to
PostScript. An important feature is that it can merge other
PostScript files into its output, permitting an author to include
figures and other graphics with text.
- Digital Volt Meter.
- Data Warehouse.
- Dielectric Wakefield Accelerator.
- Distorted Wave Born Approximation.
- Dielectric WakeField Accelerator.
- Distorted Wave Impulse Approximation.
- Dynamic Data Exchange
- See DDE.
- DYckerhoff & WIDman AG. Company that manufactures post-
tensioning and geotechnical construction systems.
- FNAL-COLLIDER detector (D-Zero).
Send corrections to email@example.com
or propose new terms for SLACspeak.