G

G     Giga, meaning 10to the 9th power, or billions of . . .(e.g.: gigabits).

G&A     General and Administrative.

G3DM     Generation 3 Dark Matter search.

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. 

Gamma, Electron, and Muon Experiment     See GEM.

GAN     GAlactic Neighborhood.

GAN     Global Accelerator Network (proposed).

GANIL     Grand 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.