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Background Rays/Frames Status

Terry Geld

Jun99 Nominal Assumptions

Developed at BR Workshop 1/15/99-1/18/99

  • Text of Witold's detailed description.
  • 0.5A in HER; 1.5A in LER.
  • Betatron collimators in S4 (LER), S12 (HER) => reject ~90% of Coulomb scatters beyond |z|=~300m; this translates to rejecting ~50% of total background.
  • No S2 collimators.
  • Total ring averaged pressures (at above currents )of 14nTorr for LER and 10nTorr for HER.

Turtle Events

Thx to T. Fieguth

  • Have 300K HER events ; Need 750K HER events .
  • Have 2.2M LER events ; Need 4M LER events .
  • Status: In continual generation.

Collimator Effects

Thx to F. LeDiberder

  • HER collimator effects available.
  • LER collimator effects available.

Zones

Thx to F. LeDiberder, S. Devmal, BkgCom group et al.

Note: zones are needed to apply the pressure profiles at mixing time.

  • HER zones available.
  • LER zones available.

Pressure Profiles

Thx to H.DeStaebler, H.Tanaka, BkgCom group et al.

  • Preliminary HER pressure profile available from 1/98, waiting for new fit for '99 IP.
  • Preliminary LER pressure profiles being tested by BkgCom group.

Status for events into bbsim

  • Minimal set of 300K HER events (needed for 250 frames) have been zoned and collimator effects applied. Zoned/collimated files are in:
    • /nfs/babar/prod/data/HER/her980930
    • /nfs/babar/prod/data/HER/her981211
    and these events are in the process of going through bbsim (thx to A. Hasan).
  • Minimal set of 1.2M LER events (needed for 250 frames) have been zoned and collimator effects applied. Zoned/collimated files are/were in:
    • /nfs/babar/prod/data/LER/ler981006
    • /nfs/babar/prod/data/LER/ler981218
    • /nfs/babar/prod/data/LER/ler981223
    • /nfs/babar/prod/data/LER/ler990127
    • /nfs/babar/prod/data/LER/ler990128
    • /nfs/babar/prod/data/LER/ler990205
    • /nfs/babar/prod/data/LER/ler990212
    • /nfs/babar/prod/data/LER/ler990216
    • /nfs/babar/prod/data/LER/ler990217
    and all these events have been processed through bbsim (thx to A. Hasan).


This page is maintained by Terry Geld (tlgeld@slac.stanford.edu)

Last modified: Tue Feb 23 13:54:08 PST 1999