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CPV#

Physics Pb-Pb runs#

Monitor if plots are not empty and timestamps are updated.

If plots are empty or not updated please inform the on-call.

If you see "Number of entries has not changed in the past cycle" but run is still ongoing then most probable reason is that PHS become busy. You can check with ECS shifter and inform the on-call if expert is not informed yet. If PHS is not busy but you see this message then inform the on-call.

If you see other red messages please check known issues. If issue is not known please inform the on-call.

[QC on QC merger node] Global CPV quality#

Please check known issues

Good plot:

alt text

The plot summarize CPV quality. If global quality is not good then please check below the details.

  • Number of digits increases assures that digits are being produced. If bad then follow the procedure above If you see "Number of entries has not changed in the past cycle".

  • Number of clusters increases assures that clusters are being produced. If bad then follow the procedure above If you see "Number of entries has not changed in the past cycle".

  • Digit occupancy check assures that digit occupancy is good. If bad then check messages on Digit Map in M2,3,4 plots and follow the instructions.

  • Cluster size check assures that mean cluster size is within allowed limits. If bad please inform the on-call. If medium - put a log entry and inform the oncall during morning and afternoon shift. No need to call during night.

  • CalibDigit amplitude check assures that observed amplitude spectra are good. If bad please inform the oncall. Medium means lack of statistics: please check later.

  • Errors presence check that occured number of errors is within limits. If not good then please inform the oncall. If medium then put a log entry and inform the oncall during morning and afternoon shift. No need to call at night if there are no other issues.

[QC on QC merger node] Global quality trend#

Good plot:

alt text

The trend shows evolution of global CPV quality. It can become not good for small portion of cycles due to fluctuations. In this case run to be considered as good.

If the trend is not good for significant part of the run then run quality must be setted to bad. Put bad flag even if issue is known. Expert will have a look and adjust the qaulity later if needed.

[QC on EPN] Error occurance#

Good plot:

alt text

If plot is not good then please inform the oncall. If medium then put a log entry and inform the oncall during morning and afternoon shift. No need to call at night if there are no other issues. No need to put bad flag for run if there are no other issues.

[QC on EPN] Digit Map in M2, 3, 4#

Please check known issues

Good plots: alt text The plots represent number of digits seen in each channel. It should be more or less uniform.

If red messages tell Hot 3G Cards (N1/N2) or Cold 3G Cards (N1/N2) then put log entry and ask the oncall to check the plots.

Bad example: HV Trip in module M2

Bad example: Number of entries has not changed in the past cycle

Minimal duration after SOR before taking any action required by these instructions: 5 min at 500 kHz

Actions to be taken by QC shifters#

  • Minimal duration after SOR before taking any action required by these instructions: 5 min at 500 kHz.
  • Inform on-call when quality is bad and it is not a known issue.

Known issues#

  • In PEDESTAL runs QC plot "Pedestal sigma distribution M3 is bad". Acording to expert, noise conditions in CPV depend on general environment in ALICE, therefore, from time to time CPV pedestals can become wider which is reflected in QC-CPV calibration run plot with the message "Number of bad pedestal sigmas in module M3 (sometimes in M2) is larger than the upper limit". This is a known issue, can be ignored, but make a log entry when it happens. See: https://ali-bookkeeping.cern.ch/?page=log-detail&id=45015

  • In PHYSICS runs Red messages on QC Plot "Digit Map in M4". Problem with high voltage is preventing this module from running normally. Experts are trying to recover. No need to report. Run quality must be setted to "good" if there are no problems with other modules. See: https://ali-bookkeeping.cern.ch/?page=log-detail&id=53523. Quality aggregator is also expected to show bad quality for Digit oocupancy check and CalibDigit amplitude check.