SLAC PEP-II BABAR SLAC <-> RAL

HEPIC E,S & H Databases PDG HEP preprints Organization Detector Computing Physics Documentation Personnel Glossary Sitemap Search Hypernews

BaBar Glossary Search Tool

M

The boost of the center-of-mass frame in the lab frame. The direction of the boost is measured run-by-run from 2-track events. The magnitude of the boost is taken from the measured PEP-II beam energies. The energies and the boost direction are stored in the conditions database.

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

Generic term for matters where the accelerator and the detector are interrelated. Often used in a context of background remediation.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Backgrounds/MDI_MTG/nextmeeting.html)

Mail stop is the mail delivery destination in SLAC. Mail stop numbers are used to identify the delivery point, such as ROB Bld 1st Fl(M/S 34); 2nd Fl, (M/S 35); Bld 280 (M/S 41).

The control room for the LINAC and PEP-II.

The primary 470MHz accelerator clock. Timing signals are derived from this clock.

mathlib is part of CERNLIB.

Reference Link (http://www.slac.stanford.edu/comp/physics/cernlib/cernlib.html)

Users who need samples of MonteCarlo events in BaBar can submit their requests to the Simulation Production (SP) system by using a web interface. The requests are then managed and assigned to production sites by using a relational database.

Reference Link (http://www.slac.stanford.edu/babar-internal/spreq/requests.html)

The work required to move a charge of one electron through a potential difference of one million volts.

Unit of energy. 1 MeV = 10^6 electron-Volts.

Reference Link (http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ev.html)

This expresses a legal arrangement between (at least) two bodies.

A meson is a particle composed of a quark and an anti-quark.
Examples include π⁺ (composed of an up quark and an anti-down anti-quark) and K^- (strange, anti-up).
BaBar studies the properties of B mesons, such as B⁺ (u, anti-b), and B⁰ (b, anti-d).

Reference Link (http://www2.slac.stanford.edu/vvc/theory/hadrons.html#Mesons)

Information which describes a set of data.

In the current release, 7.12.8, the Micro database is intended to be used mainly as a quick way of doing analysis.

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

The Micro database represents the Analysis level and contains all the information to do physics analyses. See the Workbook.

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

A measure of a computer's processor speed. Also the name of a computer processor architecture (Microprocessor without Interlocked Pipeline Stages).

Reference Link (http://en.wikipedia.org/wiki/Million_instructions_per_second)

A BaBar Event data format that stores reconstructed detector objects (hits, tracks, clusters, ...) in a compact form. The mini is described in BAD 487.

A particle, typically a muon, producing a small, nearly constant ionization along its flight path. MIPs are often used in calibration because their energy deposition in a detector is easily calculated.

The rate at which a meson (usually a B-meson) is identified with the wrong flavor (i.e. an anti-B meson is identified as a B-meson). It is important to measure this fraction for any algorithm which uses information to tag the meson flavor, since that kno wledge can then be accounted for in the final flavor measurement.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Computing/Offline/Simulation/web/mdc1.html)

In the Offline world, BaBar code is built from well defined objects called modules. Any analysis code written to interface to the BaBar Framework must be written as such a module. A module is written as a C++ class.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/framework1/framework1.html#modules)

The module talk command allows interactive changing of certain module parameters. This is the main feature that allows a user to alter analysis parameters without needing to re-compile the code.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/doc/workbook/framework1/framework1.html#modtalk)

Moose is a BaBar executable used for Monte Carlo production. It takes the place of three earlier executables, BgsApp, SimApp, and Bear, and combines all three steps (event generation, detector simulation, and reconstruction) into one package.

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

a computing method in which random numbers are generated and used to simulate physics events and detector responses.

For measurement data obtained from a computer simulation of an experiment, the Monte Carlo truth represents the actual conditions and/or parameters used in the simulation. In BaBar, the quantities represented by Monte Carlo truth include information abou t the actual particles generated by the simulation of the beam collision and the detector. Such information includes the particle types, their four-momenta and point of origin, and their decay products (if any).

Known generated values of physical parameters, used as input for the detailed simulation of the detector response, and stored as part of the simulated event data

Muon is the second flavor of charged leptons (in order of increasing mass). It has an electric charge of -1 and a mass of around 106 MeV.

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