RC meeting and Run Plan, Friday Oct. 12

Status

Beam quality
- Bottom line: things were mostly fine during swing until 11pm
- Current fluctuating at 40uA until we moved SHMS, then we requested 35uA\
- BLM trip investigation for 6 hours
- Just started data taking at 35uA again
Progress
- Finished kinematic point (theta_Shms=9.42) after 48+ hours with 46%, short of 50-60% goal
- Moved to new kinematic point (theta_Shms=6.495), need to limit current to 35uA

Rotated SHMS to 6.495deg: Encountered no issues!
SHMS HB QD alarm
- Reset QB and ramped back up
- Everything seems fine now
- Probably weather related
Hall C Dropped to Indeterminate State
- BSY3C upstream dipole dropped, triggered PSS alarm
- All the run safe boxes dropped at the same time
- Somehow, a mismatch between A-chain and B-chain caused hall to be placed in restricted access
- Led to 2h35min lost
- Unknown how this could happen

URGENT: NO TARGET OPERATOR FOR SUNDAY DAY SHIFT
SHMS at small angle (part 1)
- SHMS raw singles rates very high
  - Found to be around 700kHz at 35uA --> 80% tracking efficiency
  - Briefly ran at 30uA to see increase in efficiency when running at 15% less current --> 83% tracking efficiency (~600kHz singles rate)
  - Decided to run at 35uA
  - Took brief run during beam-tuning at 40uA --> 78% tracking efficiency (820kHz singles rate)
SHMS DC1 tripping during beam studies
- SHMS DC1 tripped when beam studies reached 50uA
- Decided to leave HV off until we are back to production running
- Instructed swing shift leader to switch back on if they (finally) finish their beam studies
- This limits what we can do during the luminosity scan
Background rates higher than initialy expected (Garth)

SHMS at small angle (part 2)
- Added during RC meeting and Run Plan, Thursday Oct. 11
- (Might) need new limits on diffusor ion chamber if we run above >=50uA (Jay Benesh confirmed might be the case), more info here.
  - Not an issue right now because we are rate-limited to 35uA,
  - Might become issue at the next momentum setting and/or the luminosity scan

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 early next week for opportunistic escorted access
- Alarm disabled for now, re-enable when fixed. Instructions

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

Continue for ~5 more shifts with Q2=3. W=3.14 x=0.25 theta_Shms=6.495
- might only reach 20-25% of statistics goal
Next setting (during weekend): Q2=5.5 W=3.02 x=0.4 theta_Shms=6.495
Prepare for 1-2 shifts of luminosity scan early next week
- Proposed to Jay to do Monday and/or Tuesday SWING when we have experienced shift crew
- Might be prudent to recruit third worker