RC meeting and Run Plan, Sunday Oct. 14
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Contents
Status
- Beam quality: noon update and last 3 hours Bottom line:
- 35uA looked fine until 03:00, beam has been terrible past this point
- Accelerator cannot deliver over 37uA at this point
- Even 37uA seems hard, we are more stable now at 35uA
- Progress
Issues: Resolved
- standard.kinematics file not updated for current run
- Finished reanalyzing runs 5078 and later during swing, estimated #lambda events doubled (in line with expectation)
- Strange NDX-PosHV alarm under SHMS HGC HV
- Steve masked alarm in the handler
- Related to a RadCon detector in the SHMS hut and not our problem
Issues: Requiring attention
Ongoing
- SHMS at small angle
- (Might) need new limits on diffusor ion chamber if we run above >=50uA (Jay Benesh confirmed might be the case), more info here.
- Added during RC meeting and Run Plan, Thursday Oct. 11
- Not an issue right now because we are rate-limited to 37uA,
- Might become issue once accelerator can deliver higher current again
- Be wary of DC trips!
- Added during RC meeting and Run Plan, Friday Oct. 12
- During luminosity scan, SHMS DCs might trip at >=50uA for one of the settings
- If we can really reach high current --> be ready to disable SHMS DCs when rates get too high (still want HMS data at those currents).
- (Might) need new limits on diffusor ion chamber if we run above >=50uA (Jay Benesh confirmed might be the case), more info here.
- HMS Dipole LN2 fill level very high (essentially full)
- Added during RC meeting and Run Plan, Thursday Oct. 11
- Not urgent, small ice ball forming in non-critical location (we're watching it)
- Cause: seems like JT-4 is stuck again
- Will coordinate with Andy Kenyon for opportunistic escorted access
- Alarm disabled for now, re-enable when fixed. Instructions
Request (non-urgent)
- RadCon wants to put a small detector in the SHMS hut during the next opportunity
- Needs few hours, communicate with Brad when next opportunity arrises
- Hall D needs opportunistic 1shift of HallC down for beam studies, not pressing right now (needs to be done before end-of-run)
- Unlikely this will happen in the next week
- Maybe when swapping out aerogel trays for the next experiment?
Plans - Physics
- Run for 5-6 more shifts with Q2=5.5. W=3.02 x=0.40 theta_Shms=6.49
- Currently 2% of statistics
- Prepare for 1-2 shifts of luminosity scan early next week (pending sufficient beam quality...)
- Maybe at least do lower points even if beam can't go up (just in case)?
- Tentatively Monday and/or Tuesday SWING when we have experienced shift crew
- Could maybe use 3rd worker to help with frequent 15min run changes.