Difference between revisions of "Recent Changes and Current Issues"

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(Created page with "* '''Do not spend more than 15-20 min trying to fix a problem'''. With any issue, contact On-Call Experts or RC. * <font color=BROWN>'''NEW: when starting a new run after a...")
 
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* '''Tagger magnet procedure:''' If the tagger magnet needs to be turned off, tell the operator to use '''only the script for degaussing, NEVER do "by hand"!'''
 
* '''Tagger magnet procedure:''' If the tagger magnet needs to be turned off, tell the operator to use '''only the script for degaussing, NEVER do "by hand"!'''
  
* '''Change of target in the hall:''' In case of questions from MCC about the necessary controlled access, refer to the logbook entry #: '''[https://logbooks.jlab.org/entry/4196113 4196113]''' for the access requirements.
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* '''Change of target in the hall:''' In case of questions from MCC about the necessary controlled access, refer to the logbook entry #: '''[https://logbooks.jlab.org/entry/4196113 4196113]''' for the access requirements. We do need escorted access when we had been at >=90nA (on the CuSn targets).
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* '''Controlled access to the hall:''' At 50-60 nA beam current, we can wait for the beacon to stop flashing (15-20 minutes) and then do not need an escort. At 95 nA beam current, the beacon will not stop flashing anytime soon, so we need escorted access, viz the ARM.

Revision as of 11:37, 5 November 2023

  • Do not spend more than 15-20 min trying to fix a problem. With any issue, contact On-Call Experts or RC.
  • NEW: when starting a new run after a successful end, do not go from Prestart, but Abort, Download, Prestart, and Go.
  • Especially after the HWP change, check the SLM and FCUP charge asymmetry (Q-Asym on Beamline Overview); the absolute values should be less than 0.1%. If they are out of range, contact the Beamline Expert.
  • NOTE: the beam position on BPM 2C21A is not essential during production; the beam orbit lock is on BPM 2H01.
  • RICH:
New RICH recovery protocol: see the "Shift Expert" tab the up-to-date information. Avoid unnecessary recoveries.
◊ RICH Sector 1 has three missing tiles; this is known, and no action by shifters is required.
  • BMT/FMT/SVT: If new hot channels appear, call the MVT/SVT/MM expert Yuri Gotra (757-541-7539). These channels need to be addressed by the expert.
Known Problem: Due to BMT SEC3 L1 subsequent trips, its HV was set to "0 V" so its occupancy plot is blank except from some noisy channels and thus looks different than the current reference run (r18663) distribution.
  • Tagger magnet procedure: If the tagger magnet needs to be turned off, tell the operator to use only the script for degaussing, NEVER do "by hand"!
  • Change of target in the hall: In case of questions from MCC about the necessary controlled access, refer to the logbook entry #: 4196113 for the access requirements. We do need escorted access when we had been at >=90nA (on the CuSn targets).
  • Controlled access to the hall: At 50-60 nA beam current, we can wait for the beacon to stop flashing (15-20 minutes) and then do not need an escort. At 95 nA beam current, the beacon will not stop flashing anytime soon, so we need escorted access, viz the ARM.