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ladebug is a GUI debugger available on OSF platforms.

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

latest is a symbolic link to the most recently built release. The only quality requirement is that the release (mostly) compiled. The release coordinator determines which release this should point to.

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

LaTeX is a typesetting program, ideal for the preparation of scientific and technical documents.

Reference Link (http://www.latex-project.org/latex3.html)

A class of elementary particles that includes the electron and its antiparticle, the muon and its antiparticle, the tau and its antiparticle, and the neutrino and antineutrino associated with each of these particles.

A lepton is a fundamental particle of which the most common example is the electron ( e^- ).
The other leptons are the muon ( μ^- ), tau ( τ^- ), and three neutrinos ( ν_e , ν_μ and ν_τ ).
Electrons, muons and tau have a charge of -1, and neutrinos have charge zero.
Each lepton has an antimatter equivalent which has the opposite charge - for the electron, the antimatter equivalent is called the positron ( e⁺ ).
All leptons have a spin of one half, and are fermions.

Reference Link (http://www2.slac.stanford.edu/vvc/theory/leptons.html)

Shorthand notation for Level-1 Trigger. This is the first stage where events observed by the BaBar dectector are flagged as being interesting enough to keep for further physics analysis. In the case of the Level-1 Trigger, this decision is made by hardwa re.

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

Shorthand notation for Level-3 software trigger. This applies further requirements through software to the events selected by the L1 trigger before they are stored.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Trigger/Level3/)

LHC++ is now called Anaphe, see there.

Reference Link (http://anaphe.web.cern.ch/anaphe/)

BaBar shifter who is posted in the MCC control room. This person provides communications between the Babar shift leader (pilot) and PEP operators and is particularly responsible for machine-detector interfaces for the shift.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Operations/shifts/shift_page_template.htm)

A calibration performed for the Electro-Magnetic Calorimeter (EMC) as part of the daily global calibration. Optic fibers carry light from a Xenon lamp to the back of the crystals while the data acquisition records the response of the system.

Reference Link (http://www.slac.stanford.edu/BFROOT/www/Detector/Calorimeter/Operations/EMC_LightPulser/index.html)

The likelihood method is a parametrized tagging method. It is denoted by the string PA in the code.

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

The LST system is the Babar IFR barrel upgrade, replacing resistive-plate chambers (RPCs) with limited-streamer tube technology.

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

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.

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

The lock server is a process running on a designated computer that manages concurrent access to a database. No data passes through the lock server, but it ensures that data within the federation is consistent and prevents simultaneous updates from multip le clients.

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

A program that is used for event collection and distribution in BaBar online data acquisition and offline reconstruction. It collects data from the online farm (L3 nodes) and writes to an XTC file. It reads XTC files and distributes events to the offline reconstruction farm.

A name which is used to uniquely identify a file, without actually being the (physical) name of the file. In BaBar we use these to provide a site-independent name for files in the eventstore.

(p0, p1, p2, p3) with metric (1,-1,-1,-1). Also known as a four-vector.

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Last significant update: 10-Sept-2002