M

M&O     Management and Operations.

M&S     Materials and Supplies.

M13     Messier 13

MA     Magnetic Alloy

MAC     Macintosh computer.

MAC     Machine Advisory Committee. (ILC)

MAC     Moves, Adds, Changes. (Telecommunications)

MAC     Most Attractive Channel

MACHe3     MAtrix of Cells of superfluid 3He.

Machine Protection System     See MPS.

MACHO     MAssive Compact Halo Object, or Massive Astrophysical Compact Halo Object

MACRO     A sequence of keyboard or touch panel operations created and saved to be initiated by one keystroke as an Operator aid. Also, a user- defined abbreviation for one or more lines of code.

MACRO     Monopole, Astrophysics and Cosmic Ray Observatory

MacSamson     A file transfer and terminal emulation program that allows a Macintosh to be used as a terminal for a host computer.

MAD     Multiple wavelength Anomalous Dispersion phasing. A primary means of solving protein structures.

MAD     Methodical Accelerator Design. A data input format for TRANSPORT.

MAGIC     Major Atmospheric Gamma Imaging Cherenkov Telescope, on the Canary Island of La Palma. 

Mail Gateway     A machine that connects to two or more electronic mail systems (especially dissimilar mail systems on two different networks) and transfers mail messages among them. 

Mailing List     A discussion group, sometimes moderated, whose messages are distributed via e-mail from a central computer which maintains the list of people involved in the discussion.

Main Beam Containment Unit     See MBCU.

Main Control Center     See MCC.

Main Drive Line     See MDL.

Main Manifold Controller     A chassis monitoring the vacuum level of a system.

Majordomo     A free mailing list server that runs under UNIX. When e-mail is addressed to a Majordomo mailing list, it is automatically re-broadcast to everyone on the list. The result is similar to a newsgroup or forum, except that the messages are transmitted as e-mail and are therefore available only to the individuals on the list.

MAN     Metropolitan Area Network. (DOE - SF Bay Area)

Management Information System     See MIS.

Manhist     Program for MANipulating HISTograms. C

Manifest     Form which indicates generator, quantity, type of waste, and disposer of waste for each shipment of hazardous wastes sent to offsite facilities.

MAP     Management Assessment Program. (SLAC)

MAPS     Monolithic Active Pixel Sensor. 

Marx Modulator     An electrical circuit designed to generate a high voltage impulse. Named for Edwin Otto Marx, who first described such a circuit in 1924.

Mask     A collimator used to shelter a detector from synchrotron radiation or other low-energy radiation. It is also used to protect detector components from direct hits by an errant beam.

Mass Spectrometer     See Spectrometer.

Master Oscillator     The oscillator generating the RF distributed by the MDL to the whole LINAC. The frequency is 476 MHz (the 6th subharmonic of the 2856 MHz LINAC klystron frequency).

Master Pattern Generator Zero     See MP00.

Master Trigger Generator     See MTG.

Material Safety Data Sheet    See SDS.

MATLAB     A matrix manipulation software package for computation and plotting.

Matrox Board     A hardware interface card, made by the Matrox Corporation, used to drive video display monitors. For example, a scrolling graphic display of both beams showing the energy and current as transmitted to MCC by the Micro FB31 from BPMs reading in a dispersion region in the arcs.

MAX II     Storage ring for electrons at MAX-lab, Lund University, Sweden.

MAX IV     Storage ring facility at MaxLab in Lund, Sweden inaugurated June 2016.

MB     See Megabyte.

MB     Maxwell-Bozmann

MBAM     Microsoft Bitlocker Administration and Monitoring.

MBCU     Main Beam Containment Unit. An interlock chassis at NPI and CID for use by the beam containment system for wide pulse beams.

MBE     Multiple beam experiment

MBE     Molecular Beam Expitaxy 

MBH     Massive Black Hole.

MBI     MicroBunching Instability.

MBK     Multi-Beam Klystron.

MBps     MegaBytes per second.

MBR     Molecular Beam Resonance technique.

MBTS     Minimum Bias Trigger Scintillators. (LHC)

MC     Monte Carlo. See Monte Carlo Method.

MC     Mode Converter

MC     Macromolecular Crystallography

MCC     Motor Control Center.

MCC     Merchant Category Code.

MCi     MegaCurie. 

MCIC     The Metals and Ceramics Center (Columbus, OH).

MCL     Maximum Contaminant Level.

MCL     Maximum Concentration Level

MCMC     Markov Chain Monte Carlo

MCNP     Monte Carlo simulation package (LANL).

MCP     Major Capital Project.

MCR     Methyl-Coenzyme M Reductase.

MCRG     Monte Carlo Renormalization Group

McT     McCallum-Turner, Inc.

MD     Management Directive.

MD     Mechanical Design. Department (SLAC).

MD     Manual Damper.

MD1     Magnetic detector at VEEP-4, Novosibirsk

MDA     Minimum Detectable Activity.

MDH4     MoDe Hutch 4. Also, MDH5, MoDe Hutch5. Aligns control of stoppers to the hutch taking beam. PHOTON

MDI     Machine Detector Interface.

MDL     Main Drive Line. A temperature-stabilized coaxial cable which carries the 476 MHz master oscillator signal, and a fiducial synchronizing signal used to unify timing of the klystrons in the LINAC and to trigger the PDUs. The length of the MDL is monitored by an interferometer, since changes in its length due to thermal changes will result in klystron phase changes down the LINAC.

MDM     Mobile Device Management.(OCIO)

MDM     Mixed Dark Matter

MDOT     MicroDOT gas chambers

MDP     Markov Decision Process.

MDRP     Millikan DRoP measurement.

MDT     Monitored Drift Tubes.

MD Time     Machine Development Time (i.e. for internal, non-user accelerator and FEL work)

ME     Mechanical Engineering. Department (SLAC).

ME2     see MEE.

MEA     Medium-Energy Accelerator.

MEC     Mission Executive Council.

MEC     Matter in Extreme Conditions or Material at Extreme Conditions.

Mechanical Design     See MD.

Mechanical Engineering     See ME.

MECi     Matter in Extreme Conditions instrument. (LCLS)

MECL     Motorola Emitter Coupled Logic. An integrated circuit technology used for fast logic boards.

MECO     Muon-to-Electron COnversion.

MEC-U     Matter in Extreme Condition Upgrade

MED     Mechanical Engineering and Design. (SLAC)

MED     Medical Department.

Medium     The material used to support the transmission of data. This can be copper wire, coaxial cable, optical fiber, or electromagnetic wave (as in microwave).

MEDSI     Mechanical Engineering Design of Synchrotron radiation equipment and Instrumentation.

MEE     Materials in Extreme Environments. (LCLS)

Megabyte     1,048,576 bytes or 1,000 kilobytes, roughly one million bytes or one thousand kilobytes.

Mega-Czar     Term used to designate person within a group who has responsibility for administration of a type of information resource, and who is authorized to appoint other czars within their computing group. See also czar.

Mega-Electron-Volt     See MeV.

Megaflops     One million floating-point operations per second. Abbreviated MFLOPS.

MEIS     Molecular Environmental Interface Science.

Melting Point     See MP.

MEM     Maximum Entropy Method.

Memorandum of Understanding     See MOU.

MEMS     MicroElectroMechanical Systems.

MES     Molecular Environmental Sciences. A discipline which uses synchrotron-based spectroscopic techniques to study environmental problems.

MESH     Microfulidic Electrokinetic Sample Holder.

MESI     Mechanical Engineering Safety Inspection.

MET     METallographic.

MET     Metrology Department (SLAC)

Meta Data     Data about data. In an electronic environment, meta data's basic elements are a structured format and a controlled vocabulary, which together allow for a precise description of a digital entity's content, location, and value.

Meter Relay     A Beam Containment module which looks at a magnet power supply to require that its voltage, as read on the meter, be inside or outside some set points. See also Beam Containment System.

Method 18     An EPA test method which uses gas chromatographic techniques to measure the concentration of individual volatile organic compounds in a gas stream.

Method 24     An EPA reference method to determine density, water content, and total volatile content (water and VOC) of coatings.

Method 25     An EPA reference method to determine the VOC concentration in a gas stream.

METSD     Mechanical Engineering and Technical Support Division.

MeV     Mega-Electron-Volt. 1 Million eV. The LINAC klystrons accelerate the beam approximately 200 MeV per station.

Mev-UED     Mega Electron Volt Ultrafast Electron Diffraction instrument (LCLS)

MEWP     Mobile Elevated Work Platform. Work surface higher than four feet, e.g. scissors lift or articulating boom lift

MEXT     Ministry of Education, Sports, Science and Technology (Japan).

MFA     Multi-Factor Authentication.

MFD     Mechanical Fabrication Department.

MFD     Multi-Function Device

MFD     Mechanical Fabrication Department.

MFD     Mechanical Facilities Department.

MFENET     Magnetic Fusion Energy NETwork. It is centered at the Lawrence Livermore Lab.

MFG     ManuFacturinG.

MFM     Magnetic Force Microscopy.

MFT     Managed File Transfer.

MFX     Macromolecular Femtosecond (X)crystallography.

MGC     Microgap Gas Chambers

mgd     Million gallons per day.

MHD     MagnetoHydroDynamics

MHS     Message Handling System. The system of message user agents, message transfer agents, message stores, and access units which together provide OSI electronic mail.

MHz     MegaHertz.

MICADO     A steering algorithm meaning in French "MInimisation des CArres des Distortions d'Orbite" which translates to Minimization of the squares of the orbit distortion. One of several methods used by the orbit correction programs at SLAC.

Microbial Action     Using the action of microbes to destroy or transform compounds.

Micromegas     MICRO-MEsh GASeous detector.

MIE     Major Items of Equipment.

Mie     A scattering spectroscopy used to study changes in the size and index of refraction of spherical and non-spherical particles whose size is within a factor of 10 from the light's wavelength. (SLAC-R -611)

Million Instructions Per Second     See MIPS.

MILNET     MILtary NETwork. Originally part of the ARPANET, MILNET was partitioned in 1984 to make it possible for military installations to have reliable network service, while the ARPANET continued to be used for research.

MIL-SPEC     MILitary SPECifications.

MIME     Multipurpose Internet Mail Extensions. A way to attach any kind of file to an e-mail message. Supersedes uuencoding in newer Unix e-mail systems.

MIN     MINute.

MinSec     Minimum Security requirements (computing)

MIPS     Million Instructions Per Second. Refers to the average number of machine language instructions a computer performs in one second.

MIRAS     Infrared microspectroscopy beamline at ALBA.

MIRI     Mid InfraRed Instrument. (JWST)

MIS     Management Information System. A formal network that extends computer use beyond routine reporting and into the area of management decision-making. Its goal is to provide the correct information to the appropriate manager at the right time.

MIT     Massachusetts Institute of Technology

Mitigation     Measures taken to reduce adverse impacts on the environment.

MITOMI     Mechanically Induced Trapping of Molecular Interactions.

MJ     MegaJoule

MKB     MultiKnoB. An operator station knob moving the field, the timing, or the phase of more than one device at the same time.

mKdV     modified Korteweg-de Vries

MKN     Maung-Kahana-Norbury.

ML     Machine Learning

ML     Microwave Lab (Stanford)

MLE     Maximum Likelihood Estimate.

MLEV     Magnetic LEVitation.

MLLA     Modified Leading Log Approximation

MLLW     Mixed Low Level Waste.

MLVR     Medium and Low Voltage Revitalization

MMC     see Main Manifold Controller.

MMF     Magnetic Measurement Facility (B081)

MMGC     Main Manifold Gauge Controller. A special gauge (one per sector) which senses vacuum for an entire sector. In the event of a vacuum leak, the MMGC sends two signals: one to the TIU, which interrupts the beam in the injector and one to the Fast Valve Controllers, whose valves seal and isolate that Sector from the rest of the accelerator.

MMI     Maintenance Management Index.

MMIC     Monolithic Microwave Integrated Circuit.

MMNTM     MoMeNTuM.

MMS     Missing Mass Spectrometer.

MMX     Matrixed Mfd technicians for X-ray operations.

MNS     Maki-Nakagawa-Sakata.

MOA     Memorandum of Agreement

MOC     Mission Operations Center (GLAST).

MOCVD     Metal-Organic Chemical Vapor Deposition.

MOD     MODel.

Modulation     A method used in modems to make data processing signals compatible with communication facilities.

MoEDAL     Monopole and Exotics Detector At the Large hadron collider.

MOJAVE     Monitoring Of Jets in Active galactic nuclei with VLBA Experiments . (US and Europe)

Moller Polarimeter     A device used to detect the degree of polarization of electrons by using a polarized target and the Moller effect.

Moller Scattering     An elastic collision between two electrons.

MOM     Momentum

MoNA     Modular Neutron Array. (NSCL)

MONALISA

MONitoring Agents in a Large Integrated Services Architecture.

MONALISA     MONitoring ALIgnment and Stabilization with high Accuracy. (AFT2 system).

MONARC     Models of Networked Analysis at Regional Centres. LHC computing project.

MOND     MOdified Newtonian Dynamics.

MONO     MONOchromator. (LCLS)

Monte Carlo method     A method of computer simulation that allows scientists to assess probable outcomes of experiments or events. The method employs repeated simulations of an event using actual data, where known, and providing probable values of unknown data. Probable values of unknown data are selected anew for each simulation by a random number generator. Based on the Metropolis Algorithm (1946).

MORSE-CG     Multipurpose neutron and photon transport code.

MORTRAN     A FORTRAN precompiler.

MOS     Metal On Silicon.

MOSG     Maintenance Operations Support Group. A SLAC operational group.

MOSS     Microsoft Office Sharepoint Server 2007.

MOST     Ministry of Sciences & Technology. (China).

MOT     MagnetOptic Trap. A combination of laser cooling using a web of laser beams and magnetic cooling using a web of magnetic fields. The web of laser beams cools atoms by bombarding them from many directions, and the web of magnetic fields induces evaporative cooling by encouraging warmer atoms to depart. Cooler atoms coalesce in the trap to form a Bose-Einstein condensate (BEC).

Motif     A GUI based on X Windows and distributed by the Open Software Foundation.

Motorola Emitter Coupled Logic     See MECL.

MOU     Memorandum of Understanding. Used by CDHS to formalize agreement between themselves and local programs with regard to enforcement of the HWCL.

MOX     Mixed-Oxide Fuels.

MP     Melting Point. The temperature at which the solid and liquid forms of a substance exist in equilibrium.

Mpc     megaparsec. One million parsecs.

MPDC     Multi-Purpose Data Center.

MPE     Maximum Permissible Exposure.

MPF     Microlensing Planet Finder. (Proposed)

MPG     Master Pattern Generator. See also MP00.

MPGD     Micro-Pattern Gas Detector.

MPIfR     Max-Planck-Institut fur Radioastronomie.

MPP     Massively Parallel Processors. For example, IBM's 9076 SP1, Thinking Machines' CM-2, and Intel's Touchstone Gamma computers.

MPPC     Multi-Pixel Photon Counter.

mppcf     Millions of particles per cubic foot of air.

MPRSA     Marine Protection, Research, and Sanctuaries Act. (Federal)

MPS     MultiParticle Spectrometer (BNL).

MPS     Machine Protection System. A system to protect the machine from damage from the beam. It uses ionization chambers, current monitors, temperature detectors, and microswitches on valves and other obstructions to rate-limit or turn off the beam whenever necessary.

MPS2     MultiParticle Spectrometer upgrade (BNL).

MPSF     MultiParticle Spectrometer at Fermilab.

MPWA     Model-dependent Partial-Wave Analysis

MQCD     M theory QCD

mQs     Millicharged particles

MR     Main Ring

MRCOFFEE     Multi-Resolution "Cookiebox" Optimized for the Future of Free-Electron (laser) Experiments

MRD     Monthly Reporting Database. (SLAC)

MRE

Meal, Ready-to-Eat (U.S. Government)

Mrem     Milli Rad Equivalent Man.

MRFM     Magnetic Resonance Force Microscopy.

MRI     Magnetic Resonance Imaging.

MRL     Minimum Reporting Level.

MRS     Monitored Retrievable Storage.

MRS     Magnetic Resonance Spectrometer

MRS     Materials Research Society.

MRS     Metal-Resistive layer-Silicon photodetector

MRST     Martin-Roberts-Stirling-Thorne

MS     Member States (CERN).

MS     Minimal Subtraction

MS     Manual Station. A manually activated fire alarm sensor.

MS     Management Systems

MSAM     Medium Scale Anisotropy Measurement

MSD     Materials Science Division (SSRL)

MSDS     Material Safety Data Sheet. An industry standard form used for listing and describing hazardous chemicals. Named changed to Safety Data Sheet (SDS).

MSE     Materials Sciences and Engineering Division (DOE)

MSG     Mechanical Services and maintenance Group. (SSRL)

MSGC     MicroStrip Gas Chamber.

MSHA     Mine Safety and Health Administration.

MSI     MicroSoft Installer.

MSIS     Management Systems Improvement Strategy.

MSL     Multilayer Soft Lithography.

MSL     Mars Science Laboratory. (NASA)

MSM     Minimal Standard Model

MSO     Management System Owner.

MSPB     Merit Systems Protection Board.

MSPs     MilliSecond Pulsars.

MSSM     Minimal Supersymmetric Standard Model

MSTR     MicroSTRategy (software).

MSW     Mikheev-Smirnov-Wolfenstein

MT     Magic Tee.

MTA     Message Transfer Agent. An OSI application process used to store and forward messages in the X.400 Message Handling System. Equivalent to an Internet mail agent.

MTB     Materials Transportation Bureau. A subdivision of DOT.

MTBF     Mean Time Between Failures. Average time a device will function before failing.

mTCA     micro Telecommunications Computing Architecture.

MTEU     Master Terminal Expander Unit. A fire alarm chassis from LARSE.

M-Theory     Posits that the strong-coupling behavior of supersymmetric string theories and field theories is governed by a web of dualities relating the different theories. This web is called M for magic, mystery, and / or membrane.

MTL     Main Test Level.

MTTF     Mean Time To Failure.

MTTR     Mean Time to Recovery

MTU     Maximum Transmission Unit. The largest possible unit of data that can be sent on a given physical medium. For example, the MTU of Ethernet is 1500 bytes.

MTU     Master Terminal Unit. A fire alarm chassis from LARSE.

MU     Mechanical Utilities.

Mu2e     Muon to electron conversion experiment. (Fermilab)

Multiknob     See MKB.

Multiple Clip     A PPS locking device which allows multiple users to lock a breaker in order to service some piece of equipment. This ensures that no one will energize the breaker while another group is still working on the equipment it powers. All locks on the multiple clip must be removed before the breaker can be energized.

Multiplex     The division of a single transmission medium into multiple logical channels supporting many apparently simultaneous sessions.

Muon     A lepton with the same charge as the electron, but with mass 210 times larger, and a lifetime of 2.2 microseconds. Because muons interact only electromagnetically, they are very penetrating. Shielding the detector from spurious muon radiation requires massive shielding. Muons were discovered in cosmic rays by C. F. Powell at Bristol in 1947.

MUSYC     MUltiwavelength Survey by Yale and Chile.

Mutagenic     Capable of causing changes in the genetic code by altering DNA.

Mutate     To bring about a change in the genetic constitution of a cell by altering its DNA. In turn, "mutagenesis" is any process by which cells are mutated.

MV     McLerran-Venugopalan

MVC     Model View Controller.

MW     MegaWatt

MWA     Management Walk-Around (SLAC)

MWH     MegaWatt-Hours.

MWPC     MultiWire Proportional Chamber.

MWTC     Multiscale Walking TechniColor

MXL     The name of a cerberus pyrotronics control panel. The term is also used at SLAC to designate the fire detection system.

MYRRHA     Multipurpose hYbrid Research Reactor for High-tech Applications. ( Planned facility in Belgium)