Using Geant4 in the BaBar Simulation

Technical Report · Fri May 23 04:00:00 EDT 2003

DOI:https://doi.org/10.2172/813141· OSTI ID:813141

Wright, Dennis H ^[1]

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1. SLAC

BABAR was the first large experiment to incorporate Geant4 into its detector simulation. Since July 2001, 1.5 x 10{sup 9} BABAR events have been produced using this simulation. In a typical e{sup +}e{sup -} {yields} {Upsilon} (4s) {yields} B{sup 0}{bar B}{sup 0} event, between 30 and 60 tracks are produced in the generator and propagated through the detector, using decay, electromagnetic and hadronic processes provided by the Geant4 toolkit. The material model of the detector is very detailed and a special particle transportation module was developed so that minute features (on the few micron scale) would be sampled in the propagation without sacrificing performance. The propagation phase for such an event requires 5 CPU seconds on an 866 MHz processor. Execution speeds for other BABAR event types will also be presented. Validation of simulated events with BABAR data is ongoing, and results of Monte Carlo/data comparisons will be shown. A discussion of the design of the simulation code, how the Geant4 toolkit is used, and ongoing efforts to improve the agreement between data and Monte Carlo will also be presented.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (US)
• Sponsoring Organization: USDOE Office of Science (US)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 813141
• Report Number(s): SLAC-PUB-9862
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
99 GENERAL AND MISCELLANEOUS
ANTI-B NEUTRAL MESONS
B NEUTRAL MESONS
COMPUTERIZED SIMULATION
DESIGN
ELECTRON-POSITRON COLLISIONS
G CODES
PARTICLE DECAY
PERFORMANCE
VALIDATION