RC meeting and Run Plan, Friday October 14th

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RC Meeting Information

Time:at 3:30pm today

  • Location: Counting house conference room

Useful Links

Current Status

Accelerator and Hall Status

  • We will take the Hall to "Controlled Access" tomorrow as soon as possible to accommodate all the work requests.
  • Since Hall B is going to be down for a while we have requested MCC to change Wien angle tomorrow to maximize the polarization to Hall A. They have agreed to do so.
  • We will stick to our previous plan to do a Moller measurement on Thursday. Should we take a mini spin dance measurement as well?
  • If we stick to 45uA then MCC will not have to do a BLA calibration to Hall A BCM on Wednesday. They will have to do it if they need to send 60uA to both Hall A and C. Should we cancel our plan to do BCM calibration on Wednesday then?
  • After a long downtime (4hrs+9hrs) we got beam back around 5pm yesterday. Then doing beam checkout and troubleshooting some BBGEM HV issue took another 3 hours. So, we could start production only around 8pm.
  • Things have been smooth since then. MCC seems to be able to send us 45uA now.
  • We had some DAQ related issues this morning but they are fixed now. Thanks to GEM folks and Alex.

Current Activity and Issues

DAQ

  • DAQ gets stuck somewhat frequently without obvious warning/error message. Shift crew gets confused and it may end up taking hours to fix. Is it possible to force CODA to throw better error messages? - Alex

Target

  • Target motion control freezes (either needs a iocha26 reboot, VMX controller reboot or a manual reset which requires an escorted access) which takes 2-3 hours to fix. Shift instructions updated to address this problem after investigation by Ellen - Arun
  • Laser interlock reset box will be installed (in between the laser room and the entrance door) by Mark Taylor tomorrow. This is to avoid depolarization of the target after a laser trip and allow a more efficient way to reset the lasers without exposing the TO to lasers while not requiring them to be laser trained. The target-on-call will be notified each time and the lasers will be enabled by the TO after consultation. A key for the entrance door will be placed in the counting room key box for TOs - Arun

Beamline

  • Dump right Ion chamber unresponsive. For now director of operations agreed to allow running with just one dump IC. - J. Kowal and team will work on it (& Compton IC) tomorrow

Run Plan

Current Plan

  • Continue taking production data
  1. 43uA of beam current | Use ps3=ps5=0, ps1=9, ps2=15, rest =-1 | One hour long runs
  2. Move the target to the pickup coil position and do an NMR sweep every 2/3 hours
  3. Return to step 1.

Requests

  • Optics runs with sieve in - Should we put sieve in tomorrow before taking beam?
  • Calibration runs on H2 - Do we have enough for this pass?
  • Moller measurement - Thursday day shift (Mini Spin dance?)
  • GEM luminosity study

Subsystems Updates

Polarized Target

  • Polarization: 42.4% (12:17pm)

Quick Summary on the performance of every sub-system during GEn

BBCAL

HCAL

BBTH

GRINCH

BBGEM

SBSGEM

DAQ

Instructions for Shift Crew

  • Keep an eye out for drifting BPM positions
  • If beam has been down due to accelerator issues perform a checkout of the beam profile by doing harp scans and check beam centering on target using the Carbon hole target, see Simona's procedure: procedure, If in doubt about whether you should go through the beam checkout procedure, call this number: 7578693131.
  • Cross check the rate with what is expected: He3, H2
  • Cross check with the expected ion chamber readings: log
  • If holding field is changed for any reason, do NOT perform an NMR measurement.

Be sure to follow these procedures:

Miscellaneous

Experimental progress (for MCC planning meeting)

  • 6.1% of accumulated charge for production data (13.55 Coulombs out of 232)
  • 32% Experimental run time (50 out of 141 days)
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