Pixel Counters Online Results

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Pixel Counters Online Results

• Igor Vasilyev
• September 13, 2001
  
  
• Current status
• all 48 octants are in readout, 99.9 of channels
  are working, monitoring is working well
• HV, thresholds, timing are selected and checked,
  no further changes in operating parameters
• PMT gain variations are below 10 over 3 months
• backgrounds are low occupancy about 0.1 per
  min_bias event
• for off-line reconstruction needed T0s, survey

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Pixel Counters Online Results

• Special runs
  Triggers min_bias mu1pix_fz
  mu1pix_nofz mu2pix_fz Two sets of
  trigger gates width (ns) 88(A), 58(B), 88(C) and
  40, 40, 46. ADC gates width 88 ns,
  TOF gate 88 ns.
• Reduction in trigger rates 2 with second set of
  trigger gates for all triggers twice less is
  background
• Muon timing peaks are clearer
• Trigger gates 40 ns (A-layer),
• 40 ns (B-layer) and 50 ns (C-layer)
• are set as defaults on September 7.
• Plan is to collect reasonable amount
• of data before October shutdown
• with these settings.

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Pixel Counters Online Results
Hit maps for pixel octants
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Pixel Counters Online Results
Timing spectra for 8 B-layer South octants
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Pixel Counters Online Results
Timing spectra for 8 C-layer South octants