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SLACspeak Terms

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P
Private (computer drive designation).
P Wastes
A federal waste list comprised of substances categorized as acutely hazardous.
P(S)
synchrotron light monitor.
P&T
Parking and Transportation or Packaging and Transportation.
P-Gun or PGUN
Polarized gun. See also PLS.
PA
Public Affairs.
PA
Preliminary Assessment.
Pa
Pascal. A unit of pressure.
PAAA
Price-Anderson Amendments Act.
PAB
Physics & Astrophysics Building (Stanford).
PAC
Physics / Project Advisory Committee.
PAC
Perturbed Angular Correlation
PAC
Physics Analysis Coordinator (BaBar).
PAC
Particle Accelerator Conference.
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.
PacMan
A concrete shielding structure at each end of the SLD detector between the endcaps and the pit walls. The two huge overlapping sections of each PacMan can be opened for access to the beam pipe.
PAD
Phase and Amplitude Detector. An RF measurement module which has been designed to measure the phase difference between two RF inputs: the signal source and the reference source. The PAD data is fed into the database after several adjustments (linearization of pad error, MDL length, upstream sources). The reference signal is usually derived from the MDL on a local reference line called PRL.
PADO
Phase and Amplitude Detector Offset. The time at which the PAD samples.
PAEC
Pakistan's Atomic Energy Commision.
PAESMEM
Presidential Award for Excellence in Science, Mathematics and Engi neering 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
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 of paleo was unearthed at SLAC in October 1964, during the excavation for the linear accelerator beam switchyard.
PAMELA
Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics.
PAMM
Planned Accessible Machine Maintenance. (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
Public Affairs Office
PAP
Performance Assurance Plan (GLAST).
PAP
Personnel Access Platform (GLAST).
PAPR
Powered Air-Purifying Respirator.
Paranoia
A VAX process that handles error messages from micros or from a SCP process that are destined either for a user or a SCP terminal. All error messages are written to the ERRLOG list which can be retrieved at any later time when investigating a fault or other action.
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.
PAT
Precision with which one measures the projected angle in two adjacent planes of a single TKR tray.
  Glast Category: hardware
Pattern Receiver Interrupt Multiplexer
See PRIM.
PAU
Pulsed Amplitude Unit. A CAMAC module used to control devices such as pulsed magnets and phase shifters which must change state at the accelerator pulse rate (up to 120 PPS).
PAW
Physics Analysis Workstation. A computer program available from CERN, PAW is an interactive utility for visualizing experimental data in a computer graphical display.
PAWN
Producer-Archive Workflow Network (NARA)
PAX
Polarized Antiproton eXperiment.
PB
Performance Baseline
PB
Pep Beamline. (SSRL)
PBC
Propane Bubble Chamber.
PBC
Package that controls the initial stage of the CPU boot process. At the end of primary boot, operators have a basic interface, which they can use to upload files, read memory, and perform diagnostics.
  Glast Category: FSW, package
PBGS
Partial Breaking of Global Supersymmetry
PBH
Pulsed Bend Horizontal. Refers to the dipole magnet used to switch electron bunches to the North Ring and positrons to the South Ring. Note that this magnet is no longer pulsed.
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
Personal Computer.
PC
Protection Collimator.
pc
Parsec. An astronomical unit of measurement equivalent to 3.26 li ght years' distance, calculated using the PARallax of 1 arc SECond .
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 capacitators 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, sub-boosters 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
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)
PCNL
President's Council on the National Laboratories.
PCON
Phase CONfiguration. The phase of a klystron taken from a model or a saved configuration.
PCR
PEP Control Room.
PCR
Polymerase Chain Reaction.
PCT
Parity Charge conjugation and Time reversal.
PCW
Process Cooling Water.
PD
Program Deputy. (MCC)
PD
Physics Discussion.
PD
Project Director.
PDB
Protein Data Bank.
PDE
Partial Differential Equations.
PDES
Phase DESired for a klystron.
PDF
Portable Document Format.
PDF
Parton Distribution Function or Pair-Distribution Function.
PDF
Powder Diffraction File.
PDG
Particle Data Group. The PDG is an international 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.
PDP-11
Programmed Data Processor. A Digital Equipment Corporation machine.
PDR
Preliminary Design Review.
PDS
Pole Divergent Subtraction
PDS
Power Density Spectrum.
PDU
Programmable Delay Unit. A CAMAC module that contains in memory a beam matrix of 256 beam code possibilities contained in 16 channels and a desired time of output pulses for each of these channels. The PDU receives the beam code from the micro and the fiducial signal from the FIDO. In this way the two data paths (timing and beam codes) meet.
PDU Channel
One of the 16 channels of a PDU.
PE
Plant Engineering. A SLAC organizational group merged under Facilities and renamed the Site Engineering and Maintenance Office (SEM).
PE&D
Plant Engineering and Design.
PE/BI
Plans Examiner/Building Inspector.
PEC
PhotoElectroChemical.
PED
Plant Engineering Department.
PED
Project Engineering and Design.
PEG
Polarized Electron Gun. A CID injector gun used to generate a polarized electron beam.
PEG
Physical Electronics Group.
PEGASYS
PEp Gas tArget Spectrometer sYStem.
PEGGY
Polarized Electron Gun (with additional gy to make it affectionate ).
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
Positron Electron Project (originally the Positron Electron- Proton Project). A 2.2km circumference storage ring at SLAC with six interaction points, two SSRL beam lines, electron-positron storage and collision capability, 4 - 18 GeV energy range, and 50 mA currents. PEP has been upgraded to be the site of the SLAC B Factory. See also PEP-II.
PEP
Project Execution Plan.
PEP II
See PEP-II.
PEP OIC
Operator-in-charge of PEP.
PEP-II
Upgraded SLAC PEP electron-positron collider. Its transformation into an asymmetric B Factory included addition of a second storage ring, as well as new beam power and control systems.
PEP-II Database
The PEP-II Project-wide Oracle-based database. It is envisioned to encompass off-line data for machine configuration and administration, as well as much of the detector counterpart data.
PEP-N
Upgrade to PEP-II (proposed).
PEP-X
Synchrotron storage ring project at SLAC utilizing PEP-II. (Propos ed)
PEPUP
PEP UPgrade.
PEP2
PEP-II (Use for Spires).
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.
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
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.
PF
Photon Factory
PFA
Particle Flow Algorithms.
PFIAB
President's Foreign Intelligence Advisory Board.
PFMON
ProFile MONitor.
PFN
Pulse Forming Network.
PGB
Pseudo-Goldstone Boson
PGM
Plane Grating Monochromator.
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 Bump
The `Phase Bump' is used to change the phase of the RF fill of an accelerator section. The general intent is to change the average phase of the RF seen by one beam, independent of that seen by the other beam. This is achieved by tweaking the phase (plus or minus) 90 degrees in the first or last 60 ns of the fill time. Currently, this method is used to adjust the energy spread of the scavenger beam.
Phase Configuration
See PCON.
Phase Decker
See Phase Bump.
Phase Jump
A Phase Shifter to compensate for the beam loading effect of the Damping ring RF cavities.
Phase Ramp
Damping Ring RF Facility for varying the phase so that the time of arrival of the extracted beam at the compressor and LI02 will be changed. Phase Ramp is moved in units of S-BAND degrees or 0.973 picosecond. Operators tweak Phase Ramp to adjust the beam spectrum and energy at the end of the LINAC, using X-ray screens in the BSY area.
Phase Raw
See PRAW.
Phase Shift Keying
See PSK.
Phase Space
A plot of the beam position versus its phase angle.
Phasefix
A system for measuring and correcting the tune of the SLC arcs.
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 Interation eXperiment is located at BNL and is investigating high energy collisions between heavy ions and protons.
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 l anguage developed by Rasmus Lerdorf.
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 Physi cs, Astrophysics and Cosmology.
PI
|The LAT Principal Investigator is the lead scientist directly responsible for completion of the project and reports directly to the funding agencies. See Dr. Peter Michelson - GLAST LAT Principal Investigator.|
  Glast Category: management
  URL: http://www.nasa.gov/mission_pages/GLAST/team/Michelson-bio.html
PI Mode
One of the two modes of bunch oscillation caused by the RF in the Damping Rings (the other one is called O MODE). In Pi mode the two bunches in a ring are opposite and oscillate toward each other (they are Pi radians, or 360 degrees out of phase with each other).
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.
PIC
Particle-In-Cell
PIC
Port d'Informació Científica. (Scientific Information Harbour)
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)
Pig
A container, usually lead, used to ship or store radioactive materials.
PIG
Package providing low-level routines for controlling the LAT power-up and LAT network configuration sequence.
  Glast Category: FSW, package
PII
Personally Identifiable Information.
PIL
See Parameter Interface Library Users Manual.
  Glast Category: software
  URL: http://glast-ground.slac.stanford.edu/workbook/pages/sciTools_pil.pdf
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 success or 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.
PIO
Public Information Officer.
PIOP
Programmable Input/Output Processor. A CAMAC module used for klystron control.
PIP
Project Implementation Plan. (ILC)
Pipeline Mode
A PAU mode of operation in which a beam code signals the PAU to act on the following beam code. This mode of operation is often used in dealing with time slot separation problems.
Piracy
Unauthorized copying of software.
PIS
Primary Instrument Scientist.
PISL
Pi-mode stabilizing loops
PITZ
PhotoInjector Test Facility, Zeuthen. (DESY)
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.
PJLZ
Parrinello-Jona-Lasinio-Zwanziger.
PKU3
Peking University 3rd. A 1.3 gigahertz TESLA-type nine-cell niobiu m 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.
PLEDGE
PoLicy Enforcement in Data Grid Environments. (NARA)
plerion
A pulsar wind nebula powered by the relativistic wind of an energetic pulsar. Often found inside the shells of supernova remnants, magnetic fields accelerate the particles, forming jets near the poles of the collapsed sta r and a ring flowing away from the equatorial region.
  Glast Category: astronomy
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.
PLO
PLant Office.
PLS
Polarized Light Source. The SLC laser Gun.
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.
PLUTO
Detector at the DORIS electron-positron collider (DESY).
PM
Preventive Maintenance.
PM
Pulsed Magnet.
PM
Performance Measures.
PM
Peripheral Monitors.
PM
Project Management.
PM
Protection colliMator.
PM
Pulse-bending Magnet.
PMAG
Pulsed MAGnets. A VAX database primary.
PMAG
Project Management 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)
PMOG
Project Management Oversight Group. (Obsolete--See PMAG)
PMS
Plant Maintenance Services.
PMS
Program Management System.
PMS
Peripheral Monitoring Stations.
PMT
PhotoMultiplier Tube. See also Photomultiplier.
PMT
|A vacuum tube that emits a large electron current proportional to the small number of photons that enter the tube.|
  Glast Category: hardware
  URL: COMMENTS=
PMU
Plant Maintenance and Utilities Building.
PMV
Pulse-bending Magnet Vertical.
PNC
Parity NonConservation, or Parity NonConserving.
PNet
Pattern Network Module.
PNGB
Pseudo-Nambu-Goldstone Boson.
PNL
An abbreviation for `Panel.'
PNNL
Pacific Northwest National Laboratory.
PNPP
Particle-Nuclear Physics Pool.
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.
POC
Publications Oversight Committee (American Physical Society).
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.
Polarized Electron Gun
See PEG.
Polarized Light Source
See PLS.
Poll 0
A VAX process which checks all SLCNET micros for database status changes and errors. If a micro is not talking anymore, it is removed from the poll list and its poll becomes `0.'
Polling
Connecting to another system to check for things like mail or news.
Polychlorinated Biphenyl
See PCB.
Pomeron
A color-neutral collective partonic excitation; the aggregate mechanism responsible for elastic scattering.
POMM
Planned Operational Machine Maintenance. (LCLS)
POOP
Principles Of OPeration. An SLC control system document.
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).
POPA
Panel on Public Affairs (APS).
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.
Positron Electron Project
See PEP.
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.
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.
Pp Beam #
The higher byte of the PPYY is the PP beam code number used by the T-Matrix to define a certain beam. This number is generated by MP00 and broadcast to all micros.
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
PPC
PEP Policy Committee. (Obsolete)
PPDG
Particle Physics Data Grid. Collaboration formed in 1999 to develop a world-wide distributed computing model.
PPE
Personal Protective Equipment.
PPF
Preprints in Particles and Fields. A weekly list of new preprints received in the SLAC Library and entered in the HEP database. Available on the web at http://www.slac.stanford.edu/library/documents/newppf.html. See also 'Anti-Preprints.'
PPL
Pervasive Parallelism Laboratory. (Stanford - Computing)
PPL
Pole PLate.
ppm
Parts per million.
PPM
Piecewise Parabolic Method.
PPM
Periodic Permanent Magnet.
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 provide stable fields and require no input current).
PPN
Parametrized PostNewtonian
PPO
Program Planning Office, an ES&H Division Department
PPOM
Pulsed Power Output Module. A CAMAC module.
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.
PPYY
A 16 bit word used by timing software and hardware to select times at which devices should be triggered on an upcoming machine pulse. It is generated at MP00 and broadcast at 360hz on the SLCNET to the various devices. It is received by the CAR in Crate 1 of a typical sector micro. PP is the high order eight bits or `beam code' used to select the time delays for devices such as klystrons and kicker magnets. YY is the low order eight bits, used to synchronize additional devices such as BPMs.
PQCD
Perturbative QCD
PQFT
Perturbative Quantum Field Theory.
PR
beam position monitor, cherenkov cell, phosphor screen.
PRA
Paperwork Reduction Act. (1995)
PRAW
Phase RAW. A database secondary. It is the raw phase measured by the PAD.
PRBs
Premeable Reactive Barriers.
PRC
PRoperty Control.
PRC
People's Republic of China.
PRCS
Permit Required Confined Spaces.
PRD
Physics Requirements Document.
PRD
Pressure Relief Damper.
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.
PREC
Physical Requirements and Exposures Checklist.
Preprint
A manuscript intended for publication but circulated among peers for comment prior to being submitted for publication.
Preprints in Particles and Fields
See PPF.
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.
PRIM
Pattern Receiver Interrupt Multiplexer. A multibus module which receives PPYYs from the CAR and interrupts the micro CPU.
PRIM-9
Interactive computer graphics program for Picturing, Rotation, Isolation, and Masking in up to 9 dimensions. Developed at SLAC in the 1970's.
Primary
A class of signal names in the VAX SLC database.
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 about 30 percent of carbonaceous biochemical oxygen demand from domestic sewage.
Princeton-Stanford Storage Rings
See Stanford-Princeton Storage Rings.
Principles of Operation
See POOP.
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
Phase Reference Line (For PAD).
PRL
Positron Return Line.
PRL
Physics Review Letters.
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.
PROD
Photon Research and Operations Division.
Production SLAC Web space
Holds all the SLAC Web pages and associated files connected to the SLAC Core Pages except Individual Home Pages. Files in the Production Space are made available to the Web by authorized SLAC WWW server that use the standard port (now 80), for example, files in /afs/slac/www served by the www host.
Production Web Pages
Pages and directories that are linked directly or indirectly from the SLAC Home Page. Production pages are meant to be viewed (i.e., they are "in production") by any intended audiences, including people outside of SLAC. See also: Non-Production Web Pages.
PROF
PROFile Monitor. A VAX primary.
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 Delay Unit
See PDU.
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.
Project M
The Stanford University project, developed by interested parties in the Hansen Laboratories and Physics Department, for the construction of a 2-mile, multi-BeV linear electron accelerator. Called Project M from 1956 - 1960, the project was renamed "Stanford Linear Accelerator Center" in 1960. The "M" stood for "Multi-Gev" and/or for "Monster."
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).
Proton-Electron Project
See PEP.
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)
PS
Power Supply.
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
Photon Science (Directorate-SLAC).
PS
Pico-Second.
PS
Program Support. (DOE)
PS
vacuum Pumping (above housing)
PS
Pressure Switch.
PSA
PCB waste Storage Area.
PSAC
Presidential Science Advisory Committee (US)
PSAD
Preliminary Safety Analysis Document.
PSB
Power Supply Board.
PSC
Planar Spark Counter.
PSC
Power Supply Controller. A single width CAMAC module used to control large power supplies. The PSC contains both a DAC and/or an ADC plus control and status bits.
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
Describes the response of an imaging system to a point source or point object. The degree of spreading (blurring) of the point object is a measure for the quality of an imaging system. See LAT Performance.
  Glast Category: astronomy
  URL: https://confluence.slac.stanford.edu/display/LSP/LAT+Performance
PSF
Point Spread Function.
PSF
Planetary Systems and Star Formation.
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
The Greek letter `y.' See also Phase Advance.
PSI
Pounds per Square Inch (unit of pressure).
PSI
Protein Structure Initiative (NIH/NIGMS).
PSI
Paul Scherrer Institute.(Switzerland)
PSIS
Photon Science Integration Study. (SLAC)
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- 30 with 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. (Proposed)
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)
PSOG
Power Supply Operations Group. Obsolete: was part of EFD.
PSR
A rotating neutron star with jets of particles streaming out from its magnetic poles. Thus, its radiation intensity varies over a regular period corresponding to the star's rotation. Radiation from some pulsars is seen only at specific intervals and not all of the time. This is known as the 'lighthouse' effect.
  Glast Category: astronomy
PSU
Programmable Synchronization Unit. Provides timing for delays longer than the fiducial period, which is about 2.8 milliseconds, or provides multiple pulses per fiducial. Used to synchronize devices to the damping ring beams. The PSU delay, period and pulse width are programmable.
PSUSY
ParaSUperSYmmetry.
PS2
high-energy Photon Science.
pT
Transverse momentum.
PTA
Projects-Tasks-Awards. (Stanford)
PTE
Potential To Emit.
PTEC
Physics Teacher Education Coalition.
PTFE
PolyTetraFluorEthylene
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.
PTT
Post Telephone and Telegraph Administration. A generic term for government-operated common carriers in countries other than the U.S.A. and Canada. Examples of the PTT are British Telecom in the United Kingdom, the Bundespost in Germany, and the Nippon Telephone and Telegraph Public Corporation in Japan.
Public Disk
A Macintosh in the computer center used as a file server for the MAC network.
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.
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.
PVSO
Pressure Vessel Safety Officer. (SLAC)
PVSS
ProzeßVisualisierungs und SteuerungsSystem, an LHC control software.
PWA
Partial-Wave Analysis.
PWC
Proportional Wire Chamber
PWFA
Plasma-based WakeField Acceleration.
PWHA
Pre-Work Hazard Assessment.
PWN
|(Also known as a plerion.) A synchrotron nebula powered by the relativistic wind of an energetic pulsar. Pulsar wind nebulae (PWNe) are believed to be powered by active rotation-powered pulsars, through a relativistic wind of p| |articles and magnetic fields and, at an early stage of evolution, are often found inside the shells of supernova remnants. The pulsar's wind is decelerated to a_sub-relativistic speed across a strong standing shock.|
  Glast Category: astronomy
PWR
Pressurized Water Reactor.
PWSA
Ports and Waterways Safety Act. (Federal)
PWT
Plane Wave Transformer.
PWU
Programmable Width Unit. A CAMAC module used for gated pulses such as gun triggers. Triggers are received from the backplane and outputs are pulsed with programmed duration.
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.
P2/E2 Plan
Pollution Prevention and Energy Efficiency Plan.
P5
Particle Physics Project Prioritization Panel.

Send corrections to jmdeken@slac.stanford.edu or propose new terms for SLACspeak.

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