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Data Challenge 2006

In 2006 a large Monte Carlo event production was started. It produced:
    o 25M+25M inclusive bb events at L=2x10³² cm^-2s^-1 and 5x10³² cm^-2s^-1.
    o 25M+25M biased bb events at L=2x10³² cm^-2s^-1 and 5x10³² cm^-2s^-1.
Many changes have been implemented compared to the DC04 data challenge. In general, the performance is slightly degraded as a result of a more realistic simulation. For instance, the number of IT clusters is increased by roughly 30%-40%. In the TT the increase is about 17%.
There is a nice DC06 summary page from Thomas Ruf.
See also the DC06 tracking wiki

Talks on ST performance

• First look at data, M. Needham, Software week, 26 April 2006.
• ST performance, M. Needham, T-Rec meeting, 27 March 2006.

Changes for DC06

• New, more realistic material descriptions (XML) for IT and TT:
  • Detailed description of the modules.
  • Rough estimation of material outside acceptance (e.g. TT frame).
  • Material more inhomogeneously distributed.
  • More material at high rapidity in TT (e.g. beam pipe insulation).
  • More material in IT cable region
  • More detailed description of IT cooling
  • Material of radiation monitor
  • Tilt of IT with respect to the LHCb coordinate frame implemented.
• New DetectorElement code (following the new XML description).
• Digitization
  • 1% of dead strips
  • Signal in e- calculated using 2003-160 (more accurate than G4)
  • Capacitive loads of 38 - 56 pF (TT) and 18 - 37 pF (IT)
  • Noise in e- parametrized as function of capacitance:
    • 780 + 48*C [pF]
    • S/N cut in clustering 3.6, high threshold S/N of 8.
  • Capacitive coupling parametrized as function of capacitance.
    • 0.08 + 0.09*C [pF]
    • Not so physical...
  • Charge sharing/ charge loss from old 2002 testbeam data
  • Spillover
    • Data from Laser tests in 2003 (TT: Vfs 400, IT: Vfs 0 L/R, 400 T/)
    • TT remainder: data for capacitance 36 - 57 pF available pick closest (36 % or 43 %). Generally few % optimistic (DC04 43 % everywhere)
    • IT remainder: 26% (T/B) and 25% (L/R). Aggressive strategy, notice the inconsistency.
    • Time of flight properly taken into account
    • Different pulse shape for capacitive coupling properly taken into account (reduces spillover).
  • New channel numbering scheme
  • New data format

• New beam pipe description: all Beryllium, new flanges and support wires.
• New magnetic field map
• Additional envelopes in XML to speed up the TransportSvc
• Move to Mathcore and SMatrix packages
• New track event model
• New PAT packages, new C++ seeding
• Fitting in tilted geometry