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B

Refers to physics involving fully reconstructed B candidates, both B+ and B0. There is a software package, BRecoUser, associated with this topic. The relevant analysis working group is the EHBDOC AWG.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Physics/Analysis/AWG/EHBDOC/EHBDOC.html)

The analysis procedures used to distinguish decays of b quarks from decays of anti-b quarks.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Physics/Tools/Tagging/Main/index.html)

anti B meson.

Major particle of study for the BaBar collaboration. Contains one bottom quark and either a up quark (charged-B) or a down quark (neutral-B). At the BaBar detector, the B-mesons are daughter particles of the Upsilon (4S) particle.

Neutral B meson composed from a quark d and an anti-quark b

B and B-bar experiment.

Reference Link (http://www.slac.stanford.edu/BFROOT)

c++ is the programming language adopted as the main one in the official BaBar code.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Computing/Programming/ProgC++class.html)

Babar Conference Room is P&E Bld (Bld 280), Rm 162 (12 people). Contact Kazuko Onaga, x4625 or Kathy Webb, x2363.

Reference Link (http://www.slac.stanford.edu/gen/pubinfo/slaconly.contact.html)

The reference link below points to a BaBar detector image gallery.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Images/Images.html)

This is an operations software tool used to interface with PEP-II. It is an EPICS application.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Operations/EPICS/cen-bip/http/bipMain.html)

The BABAR acronym, which is the name of the experiment and detector collaboration, refers to the B/B-bar system of mesons which are produced at SLAC's PEP-II collider. Babar and the distinctive likeness are trademarks of Nelvana and are used with permission. (TM & ? Nelvana, All rights reserved.)

Reference Link (http://www.slac.stanford.edu/BFROOT/BABAR.html)

BABAR Notes consist of technical and non-technical memos on all manner of subjects relevant to the BABAR Collaboration. Topics include physics at the PEP-II collider, detector design, simulation, collaboration issues, etc.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/attic/BaBarNotes.5feb99)

BaBar Object-Oriented Geant4-based Unified Simulation, (BOGUS), is the BaBar fast- and detailed-simulation layer over Geant4 running in the BaBar Framework.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/sim/sim.html#bogus)

The logbook (which for BaBar exists as a computer file) in which the physicists on shift keep track of the daily operations, ie status of beams and detector, data taken etc.

BaBar Analysis Document - Frequently updated internal Babar documents available to BaBar collaborators. BAD notes are generally an individual's or group's work in physics analysis, detector performance, analysis tool documentation, upcoming conference ta lks, or drafts of soon to be published papers.

Acronym for BaBar Analysis Documents

Reference Link (http://www.slac.stanford.edu/babar-internal/BAD/doc/index.html)

Unit of scattering cross section. This is the number of particles scattered into a solid angle per unit time and then divided by the incident intensity. 1 Barn equals 10^(-28) m^2.

Central portion of the BaBar detector. Contains, within the super-conducting magnet coil, the silicon vertex detector, the drift chamber, the DIRC (ring imaging Cherenkov detector), electromagnetic calorimter and cylindrical resistive plate chambers. This is all located inside the 18 layer of steel of the flux return. Between the layers of steel are currently located resistive plate chambers. (The link is to the Technical Design Report, which contains drawings of the parts of the detector.)

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/TDR/)

This is the specific I/O Board used in the barrel region of the EMC DAQ system. The EMC DAQ system uses a different I/O board in the end-cap region, see EIOC.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/DAQ/Calorimeter/WriteUps/IOB.pdf)

A test release is based upon the a specific production release which is the base release.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/srt1/srt1.html#using_srt)

The fundamental unit of persistent data is a basic object.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/objectivity1/objectivity1.html#terms)

Interactive processing is intended for those activities that truly require user interaction, e.g. debugging, or are very short.Other jobs should be submitted by batch. This includes but is not limited to CPU intensive jobs. The batch utility reads comman ds to be executed at a later time. Batch jobs are usually submitted to a special queue, specifically for batch jobs. Batch jobs will be submitted to the batch queue for immediate execution.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html)

anti B meson.

TCL control file for BetaApp which is used to read the micro level information into Beta application for analysis.

See "beam energy substituted mass"

The Bear application runs the full BaBar reconstruction chain, invoking the reconstruction modules within the SVT, DCH, DRC, EMC and IFR sub-systems. The output from Bear is designed to be used in physics analyses.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/reco/reco.html#bear)

A basic reconstruction output format based on RogueWave and used for MDC 1. Beast is now obsolete.

Detector at KEK-B storage rings for study of CP violation using B-mesons.

Reference Link (http://belle.kek.jp/)

Beta is an analysis toolkit for use with BaBar data. It forms the basic interface to the complete reconstruction of BaBar data. The primary goal of Beta is to provide a simple, common basis for writing detailed physics analysis programs.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html)

An electronic system in the BaBar counting room which activates a siren in case of serious malfanctioning of the detector.

A Beta Candidate is a representation of what is known or assumed about a (alleged, thus candidate) particle. Candidates are represented by the BtaCandidate class, and contain the mass, momentum, geneology (mothers and daughters), vertex information, etc., for the hypothetical particle.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html)

A Beta Candidate is a representation of what is known or assumed about an (alleged, thus candidate) particle. Candidates can represent various levels of processing, various data types: a reconstructed object, a combination of candidates, a transformation of a candidate for a few examples. Candidates are represented by the BtaCandidate class.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html#candidates)

A Beta Operator can combine one or more Beta Candidates to form new ones. Vertexing, mass constrained fitting, and simple 4vector addition are all operators.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta2/beta2.html#operations)

Beta* is the value of the beta function (accelerator lattice function) at the interaction point. There are four different beta*'s, a horizontal and a vertical for each beam.

The betarun* script facilitates running the BetaApp executable.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html)

A package providing a set of tools for use in Beta level analysis.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Physics/Tools/BetaTools/BetaTools.html)

BetaUser is a package that has been created to facilitate a user's interaction with the larger scale Beta package. The BetaUser package, which makes the BetaApp executable, is where individuals can develop their own analysis.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html)

BFDIST is a UNIX environment variable that is set to point to the top of the directory tree containing production releases and packages. The default is $BFROOT/dist. SoftRelTools uses this variable to locate the production releases on which users base their test releases. It must contain two directories: packages and releases.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/srt1/srt1.html)

BFMAIL allows you to send email to centrally managed BaBar mailing lists.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/info_resources/info_resources.html#bfmail)

The bfreport command reports information from the PRV0 production database. Use it anytime you want to find the name of a collection of interest.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/find_data/find_data.html#bfreport)

BFROOT is a UNIX environment variable that is set to point to the top of the BaBar file system. Most references to the BaBar file system should be made through this environment variable. In this way users are protected from changes in the physical locati on of the disks.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/srt1/srt1.html)

The "BGFilter" is a software filter used in Prompt reconstruction. It is run after track reconstruction in the drift chamber and cluster finding in the calorimeter, but before full reconstruction. The filter is fully documented in BAD 194.

Reference Link (http://babar-hn.slac.stanford.edu:5090/babar-internal/BAD/doc/detail.html?docNum=194)

BGFMuMu is a tagbit used to identify events which pass the background filter (BGF) and are identified as dimuon (e+e- -> mu+mu-) events. These events are used primarily for calibration.

simulation executable built on the Geant4 toolkit which takes four-vectors from an event generator and propagates them through the detector, producing GHits. The detector geometry is also built in BgsApp.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Computing/Offline/Simulation/web/bogus-guide.html)

An event in which an electron and positron scatter from one another (Bhabha scattering). Such events are backgrounds in the BaBar detector and are used for calibration.

In bhabha scattering, an electron and positron annihilate to form a photon, which in turn creates another electron positron pair.

A binned likelihood fit is a fit to a binned distribution (histogram).

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Physics/Analysis/Statistics/Report/report.pdf)

A Unix command that returns the status of a users batch jobs.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html#bjobs)

A Unix command for killing a batch job.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html#delete)

Power loss to SLAC site. BaBar has procedures to deal with this (see link).

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Operations/CareAndFeeding/care/node135.html)

Please see Blind Analysis.

Reference Link (http://www.slac.stanford.edu/babar-internal/BAD/doc/download.html?file=00091.002.ps)

To boost a BtaCandidate from one frame to the other, you can use a BtaBooster, which comes from the BetaCoreTools package. The link gives additional information about accessing the machine boost and other beam parameters.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Physics/Tools/PepBeams/#access)

Creating a new federation generates a Boot File. The Boot File describes the federated database configuration, its own location and file server, the FDID, lock server node, and other parameters describing the federation. By BaBar convention this fil is named BaBar.BOOT.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/objectivity1/objectivity1.html#terms)

A Unix command to peek at the output of a batch job in progress.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html#output)

A Unix command that returns a list of available batch queues.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html)

Radiation is emitted when charged particles are accelerated. When a charged particle passes through the field of atomic nuclei, it emits radiation and loses energy in the process (Bremsstrahlung is German for decelerating-radiation)

When power available to SLAC is reduced because of grid production limits, the site undergoes a brown out where large electrical power loads (eg, accelerator, BaBar systems) are shed. BaBar has procedures for this situation (see link).

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Operations/CareAndFeeding/care/node135.html)

When power available to SLAC is reduced because of grid production limits, the site undergoes a brown out where large electrical power loads (eg, accelerator, BaBar systems) are shed. BaBar has procedures for this situation (see link).

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Operations/CareAndFeeding/care/node135.html)

A day during a period of data taking in which the accelerator operations are stopped, due to a high demand for electrical power - typically from many air conditioners on in hot summer days - from the SLAC power provider.

A Unix command to command to submit batch jobs.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/batch/batch.html#bsub)

A BtaCandidate is a Beta level representation of a possible particle candidate. The workbook has more details.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/beta1/beta1.html#basics)

Skim defined by SemiLeptonic Analysis Working Group. It contains B -> D(*)(*) l nu events

Reference Link (http://www.slac.stanford.edu/~jack/recoil/dlnuskim.html)

A buffer is used to help eliminate latency is a system by having a number of transactions being able to occur without waiting of something else keeping up.

Many builds are done of the BaBar software. There are various kinds, online, offline, dataflow, physics, lettered and probably some others. Most of these will end up under $BFDIST.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Computing/Offline/SoftwareAdmin/SoftwareAdmin.html)

Group of crystals in the calorimeter (EMC) where a particle has deposited some energy.

The program the accelerator operators use to control injection. It shakes hands with the BISM.

This EPICS function manages the interaction between BaBar and PEPII from the BaBar side.

To add an entry to the Glossary use the BaBar Glossary Submission Form.

All comments, requests, and corrections are welcome. Send them by e-mail.

Last significant update: 10-Sept-2002