Status of ' and SMT rad status

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Status of .and SMT rad status
Delivered 10.4 pb-1 Recorded 9.2 pb-1 16 M
events Efficiency 88.5
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(No Transcript)
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PDT021
PDT021 failed. Runs are flagged for degraded
muon quality. Needs opening the detector for
repair ? 8h access on Wed.
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More issues

• Last night a powers supply for the trigger
  framework failed. "On a positive side we have
  had good spare, clear instructions how to
  proceed, clear labeling of all cabling, which
  make replacement easy."We have issues with
  calorimeter since (high noise).
• Dropped interlocks...
• Thursday quench25 rad to 50 rad from the BLM.

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• Bias voltage is the limiting factor
• Breakdown of coupling capacitor and
  micro-discharge

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• damage constant (time and temp dependent)
• flux (1 MeV n/cm2)
• V Volume

Known
DIleak a F V
Current
Measured
Luminosity
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at 2.7 cm
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F-Wedge noise (Micron wedges) 15 of the r/o
channels
work in progress
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Disabled HDIs
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Conclusions

• D0 was running well last week, but we need now to
  open the detector to fix a PDT and have some
  calorimeter issues.
• We are assessing the D0 status with respect to
  aging/radiation.
• SMT radiation monitoring is in place(includes a
  beam abort).
• We do not see unexpected radiation effects, but
  we are only at the beginning of the lifetime.
• The number of disabled HDIs in the SMT needs to
  be understood.