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L&EO
|The launch and initial checkout period of up to 60 days, during which the GLAST spacecraft, GBM, and LAT are brought up to full operating status and verified. The end of L&EO is the hand- off of the GLAST from General Dynamics t| |o NASA.|
  Glast Category: operations
LA
License Application.
LA
Liquid Argon.
LAA
Lepton Asymmetry Analyzer.
LAA
Local Administering Agency. (CH&SC Sec. 25500 et seq)
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 .
LAC
Liquid Argon Calorimeter. A SLD detector system. See also Calorimeter.
LAD
License Application Design.
LAER
Lowest Achievable Emission Rate. (from CAA)
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 cospological 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).
Landau Damping
Obsolete. See BNS Damping.
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, home of the LANL eprint archives at http://xxx.lanl.gov.
LAPP
Laboratoire d'Annency-L
LAR
Large Adaptive Reflectors.
LAr TPC
Liquid Argonne Time Projection Chamber.
Large Power Supply
See LGPS.
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.
Laser-wire
A high-powered laser beam focused down to the smallest spot possible and used in the SLC to measure the size of the interaction point. The SLC laser-wire, commissioned in July, 1996, replaces conventional wire measures, which break apart from thermal shock at high beam intensities.
LASS
Large Aperture Superconducting Solenoid spectrometer at SLAC. A decommissioned ESB experiment.
LASS
LASer analyzing Station. A B-line apparatus.
LAT
Local Area Transport.
LAT
Large Array Telescope (GLAST).
LAT
A Gamma-ray telescope designed to measure the energy and direction of Gamma-rays incident from space with energies from about 20 MeV to greater than 300 GeV. Objectives include: the study of the mechanisms of particle acceler ation in astrophysical environments: study of AGN, pulsars, and supernova remnants: the resolution of unidentified galactic sources and diffuse emissions from cosmological sources: and the determination of high-energy behavior of GRBs and transient sources. Main components include a silicon-strip track detector, a calorimeter, an anti-coincidence detector, and a data acquisition system.
  Glast Category: hardware
LATC
Package that provides a framework for controlling configuration of the LAT's detector electronics. In flight, LATC reads configuration parameters from binary files stored in EEPROM and manages the internal LAT network comman d sequences needed to set hardware registers to the specified state.
  Glast Category: FSW, package
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.
LAVC
Local Area VAX Cluster.
LBL
see LBNL
LBL
Low-energy cut-off BL Lac object.
LBNE
Long-Baseline Neutrino Experiment. (FermiLab)
LBNL
Lawrence Berkeley National Laboratory, CA. Full name of lab is Ernest Orlando Lawrence Berkeley National Laboratory.
LC
Linear Collider.
LC
Liquid Crystal.
LCA
Laser Controlled Area.
LCAT
Package containing tools for defining the structure of CCSDS command and telemetry packets consumed and issued by FSW systems.
  Glast Category: FSW, package
LCB
Lat Communications Board.
LCBD
Package providing driver software to control each CPU's LAT Communications Board. The LCBD driver controls how internal commands are sent between CPUs, and how commands are sent from the Spacecraft Interface Unit to the LAT electronics. The LCBD driver also handles event data packets as they are delivered by the hardware.
  Glast Category: FSW, package
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.
LCI
Package used by operators to inject charge into the LAT front-end electronics. Data resulting from this procedure are used on the ground to calibrate the front-ends.
  Glast Category: FSW, package
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.
LCM
Package installed on each CPU that allows operators to collect CPU diagnostic data, dump FSW task and module listings, and set low-level FSW behavior.
  Glast Category: FSW, package
LCPC
Laboratory Computer Policy Committee
LCS
Laser Cavity Shutter. A PPS device used to stop the PLS laser whenever the laser room door is opened.
LCS
Package in the FSW abstract communications layer that controls how data packets received and sent via the LAT Communications Board driver are routed to FSW tasks.
  Glast Category: FSW, package
LCS
Laser Compton Scattering.
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 project.
LCWS
Linear Collider WorkShop.
LDA
Large Aperture Dipoles.
LDA
Local Density Approximation.
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.
LDR
Land Disposal Restricted (Land Ban).
LDRD
Laboratory Directed Research and Development.
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.
LEA
Local Enforcement Agency (for solid waste in California).
LEACH
Local Electronics And Cryogenics Housing.
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 .
LEAR
Low Energy Antiproton Ring (CERN)
LEB
Low Energy Beam.
LEBC
Little European Bubble Chamber (CERN)
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.
LEEP
Laboratory Electronics Equipment Pool.
LEET
Large Energy Effective Theory.
LEFF
The effective length of a magnet in meters. A SLC VAX database secondary.
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.
LEM
Linac Energy Management. A VAX procedure used to adjust the LINAC quadrupole focusing strengths to match the changing beam energy profile. The beam energy varies as klystrons trip off, or their phases are changed.
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.
LEO
|Also known as L&EO. The launch and initial checkout period of up to 60 days, during which the GLAST spacecraft, GBM, and LAT are brought up to full operating status and verified. The end of L&EO is the hand-off of GLAST from Ge| |neral Dynamics to NASA.|
  Glast Category: operations
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).
Level 0 processing
Processing of level 0 data delivered by the MOC into a form which can be displayed and trended (e.g., LAT housekeeping data) or injected into the Level 1 processing pipeline (LAT science data). Consists of rece iving and unpacking MOC Level 0 transfer packages, storing LAT telemetry packets on disk and logging their arrival, and (for science data) reassembling a merged set of event data from all EPUs that can be fed into the data processing pipeline.
  Glast Category: data processing
Level 1 processing
Processing of level 0 data into level 1 data. Consists of creation of a database of reconstructed Gamma-ray and cosmic ray events.
  Glast Category: data processing
LFD
Light Front Dynamics
LFIC
Laser Feedback Intensity Control. A feedback system designed to compensate for the loss in laser light intensity of the PLS.
LFL
See LEL.
LFO
Laboratory Financial Operations.
LFS
Package for managing the onboard EEPROM file system: allowing operators to upload and delete files, create and delete file directories, dump file contents into telemetry, diagnose the file system, etc.
  Glast Category: FSW, package
LFTD
Light Front Tamm-Dancoff
LFV
Lepton-Flavor-Violating/Violation.
LGO
Lunar Geoscience Orbiter.
LGPS
LarGe Power Supply. A database primary. Each LGPS is controlled by a CAMAC module (PSC).
LGT
Lattice Gauge Theories
LHC
Large Hadron Collider (CERN).
LHCb
Large Hadron Collider beauty experiment. (CERN)
LHK
Package that streams hardware and software health and safety and low-rate science data into telemetry: also allows operators to define red limit engineering thresholds, which - when exceeded - result in transmission of real-t ime telemetry alerts.
  Glast Category: FSW, package
LHT
Liquid Hydrogen Targets.
LHW
Liquid Hazardous Waste.
LH2
Liquid Hydrogen.
LI
Abbreviations for Linac.
LIAR
LInear Accelerator Research code. Accelerator structure design software.
LIARP
LInear Accelerator Research code Parallel. Accelerator structure design software.
LIB
LIBrary.
LIC
Line Item Construction.
Lichtenberg tree
Or Lichtenberg Diagram. See Beam Tree.
LIGO
Laser Interferometer Gravitional-wave Observatory
LIL
Linac Injecteur de LEP.
LIM
Package that controls the LAT's operating mode and manages both commanded and automatic mode changes: also ensures that the LAT detector and FSW maintain a proper state as mode changes occur.
  Glast Category: FSW, package
LIN
Abbreviation for Linac.
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.
LINE
An Interactive Graphics Program.
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 hanrware 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.
LIRIC
Linac Improvement and Reliability Investigation Committee.
LISA
Laser Interferometer Space Antenna
LISOC
|Please refer to ISOC, the preferred acronym for the LAT Instrument Science Operations Center._|
  Glast Category: organization
  URL: http://glast-isoc.slac.stanford.edu/
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 Water Acts. 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.
LITA
Library and Information Technology Association.
Little-endian
A format for storage or transmission of binary data in which the least significant byte or bit comes first. See big-endian.
LLD
Lower Limit of Detection.
LLL
See LLNL.
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 c ontrolling the phase and amplitude of RF signals at low power leve ls, before they are amplified to high power levels.
LLS
Synchrotron Light Laboratory (Spain).
LMA
Large Mixing Angle.
LMAC
LEP Machine Advisory Committee.
LMC
Large Magellanic Cloud.
LMC
Package allowing operators to request telemetry streams that contain low-rate science data from the ACD, TKR, and CAL subsystem electronics.
  Glast Category: FSW, package
LMP
Lightest Messenger Particle.
LN
Liquid Nitrogen (tank).
LNF
Laboratori Nazionali di Frascati. (INFN)
LNLS
Laboratorio Nacional de Luz Sincrotron (Brazil).
LNS
INFN Laboratori Nazionali del Sud, Italian laboratory located in Catania.
LNW
Lehmann-Newton-Wu
LO
Leading Order.
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)
LOF
See Instrument Science Operations Center's (ISOC) website.
  Glast Category: operations
  URL: http://glast-isoc.slac.stanford.edu/
LOFAR
Low Frequency ARray.
LOI
Letters of Intent. (ILC)
LOIS
Loss Of Interim Status.
LOLA
S-band transverse deflecting structures. Named for creators Greg L oew, 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.
LOS
Laboratory, Office and Shops building (SSRL).
LOS
Level Of Service.
LOS
|Routine orbital event at which GLAST loses communications with a TDRSS satellite or with a ground station.

|
  Glast Category: operations, spacecraft
LOS
LockOut Stop.
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
|Package controlling the LAT's core science functions: collection and filtering of event data: packaging of Gamma-ray, heavy ion, and minimum ionizing particle event candidates into science telemetry: detection of GRBs and trans| |mission of alerts and autonomous repoint requests.|
  Glast Category: FSW, package
LPA
Large Piwinski Angle.
LPC
Laser Pulse Chopper.
LPC
LHC Physics Center.(Fermilab)
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
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.
LRP
Long Range Plan (DOE).
LRS
Local Rotational Symmetry
LRS
|Data acquisition program of the LAT when passing through the SAA.|
  Glast Category: operations, spacecraft
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.
LSF
Load-Sharing Facility. (Computing)
LSH
Level Switch High.
LSI
Large-Scale Integration.
LSL
Level Switch Low.
LSM
Package that receives timetone, attitude, and 'ancillary' message packets sent periodically by the Spacecraft, as well as a once-per-second hardware time signal, from which it constructs internal tables correlating Spacecr aft time and internal LAT system time for use by other FSW systems..
  Glast Category: FSW, package
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
Laser Safety System. A system of interlocks around a secured enclosure to protect personnel from laser light.
LSS
Large Scale Structure
LSST
Large Synoptic Survey Telescope.
LST
LoST Phase. A klystron summary status indicating that the PAD is not able to measure the klystron phase.
LST
Limited Streamer Tubes. (BaBar)
LSZ
Little String theory.
LTB
Lemaitre-Tolman-Bondy
LTC
Package that monitors data collected by thermal sensors on LAT, executes a control algorithm based on this input, and turns heaters on and off. LTC is responsible for fine-tuning the thermal control of the LAT and minimizing thermal distortions.
  Glast Category: FSW, package
LTD
Low-Temperature Detectors.
LTDA
Long-Term Data Access. (BaBar)
LTE
Long-Term Exposure (photography)
LTMR
Low Temperature Materials Research Group (SLAC)
LTR
Linac To Ring.
LTR
Low Temperature Materials Research.
LTR
Low Temperature Reservoir.
LTU
Linac-To-Undulator.
LTX
Package providing the framework for unit, functional, and acceptance testing of LAT Flight Software.
  Glast Category: FSW, package
Lucretia
A physics toolbox for the simulation of high-performance single-pa ss 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.
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.
LWC
Lost Work Cases.
LWFA
Laser WakeField Acceleration
L3
Detector at LEP (CERN).

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

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