RC meeting and Run Plan, Wednesday December 15th

RC Meeting Information

Run Coordinator: Brian Quinn

Location: Counting House Conference Room

Time: 3:15PM

Remote connection link: https://bluejeans.com/256205934

Toll-Free Number (U.S.& Canada): 1-888-240-2560

Bluejeans Meeting ID: 256 205 934

Upcoming Shifts Which Need Filled

No vacant shifts remains until the winter break shutdown:

Thanks!!! to Thir, Scott, Nathaniel, Maria, Bob, Sean, Albert, and Zeke!!!... and especially Kondo who filled in for Saturday day, at short notice, allowing us to keep running!! ... and to Alexandre for filling two of the final 3 shifts... and to Arun who took the last shift.

But, LOTS of empty shifts in January. And NEW PLAN FOR BEAM TO HALLS... Starting Jan 11 Swing !!!!

I've added shifts to schedule starting Jan 11 Swing for SL and starting Jan 10 Day for TO. (Cooling of target not yet scheduled.)

Today's estimate: Optics beam Tue. Jan 11, "Bonus beam" Jan 12-16. Official beam Jan 17

Accelerator and Hall Status

• ~75 ns shift in all trigger-related timing!!!!! (ADCs, GEM timing)
  • Cause???
  • Latency values for all ADCs adjusted by Alexandre
    • Except fiber 21 which was 112 instead of 119 from 17:17 last night until 14:20 today
• End of beam: Tue. Dec. 21 at 7:00 AM

To be Done During Extended Down Time

• Replace J0 INFN plane with UVa plane

Run Plan

• Return to 12M on LH2 per cycle
• Doing LD2 for "Cycle 19"
  • Continue following cycle pattern and ticking off runs-completed on paper copy at SL desk

Opportunistic Access Completed

• Put network-readable 'scope on trigger signals to quickly identify 70 ns timing shifts. (Alexandre) Done
  • Are meaning of scope traces in Logbook? ... and what changes to look for? ...I can't find the log entry.
• Remove unused HV card from HV mainframe for hodoscope (Done, by Alex)
• GRINCH Changed from 4-LED system to 1-LED system. Turned down brightness to get ~ 1 p.e. (Todd/Maria)
• Test HCal pulser and make measurements with difference latency (Scott & Sebastian) Done ... (But then timing changed???)
• Reboot rpi 18 for BBCal HV mainframes that haw been giving trouble (Sebastian)
• Replace Vetroc in slot 6? crate 6? (Bryan/Alexandre) Done??????
• And the big remove GEM J2 plane without opening truckramp! (Holly & Zeke) Done

Resolved Issues

• No longer reset/configure/download for each run
  • But be sure to Config/Download if values change
• Hodoscope HV crate internet function restored (Kate found it had lost momory of it's address etc.)
• HAREBOOT Passwords ...found. Will be posted on paper beside whiteboard.

Unresolved Issues

• Occasional timing shifts of ~70 ns  !!!!!!!!
  • maybe seen only twice? .... Well, 3 times now!!!
    • Bryan and Alex think it is OK to skip Reset(s), Configure, and Download. Just Start run (or Prestart and Go if you have some reason to wait).

Subsystem Updates

1. HCal
1. F1 errors (HCal sync errors)... Don't ignore!! End, Reset(twice?), Configure, Download. If that doesn't work, call Alexandre. One happened this morning.
2. Correlation plot of HCal ADC time and HCal TDC gives clear sign of 70 ns shift in either ADC or TDC... Andrew added this to the critical plots.
3. Binder of good and bad HCal plots for LH2 and LD2 target will be put in CH... Sebatian now has the binder.
4. Sebastian is working on list of runs with timing shifts. Bryan thinks there were only 2 (now 3!!) real ones many of remainder caused by SL seeing timing peak of LEDs when beam is off.
5. During access, LED trigger timing was adjusted to position LED pulse well in ADC window, but then it was necessary to change ADC latency to position HCal signals, knocking LEDs out of window.
6. Level-1 accept from upper HCal crate was supplied to Alexandre's network oscilloscope yesterday.
2. BBCal
1. Many HV communiction issues, may have been fixed by boot of rpi 18
2. Andrew is worried that BBCal rate does not scale linearly with beam current. Seems to go UP more than proportionally with current for change from 1 uA to 12 uA... may be result of measurement errors at low beam current.
3. Alexandre and Bogdan are worried BBCal trigger rate has increased without change of threshold
3. Timing Hodoscope
1. David Hamilton reports Rachel is making progress since discovering left TDC copy of RF signal had a problem. She will report on status in an RC meeting in the near future.
2. Kate has revived HV network connection.
4. GRINCH
1. Maria is changing HV to gain-match the tubes. Used the DAQ during access. Changed to 1-LED system instead of 4-LED system.
5. GEMS
1. Fiber 21 had wrong latency value (112 instead of new 109) from when latencies were changed after accessss (yesterday ~17:20) to today ~14:20 <\li>
2. There are no plans to take out all GEMs over Dec.-Jan. break. Some electronics will be disconnected to allow GEMs to be slid to side for access. Support for J0 4-slot backplane will be replaced with 3-slot backplane.
3. J0 layer will be replaced by a UVa layer. J2 frame is being attached to UVa layer.
4. Andrew believes it is worthwhile to turn on J0 top. Zeke agrees and has tried. A low-voltage problem was encountered, which was addressed during access by cycling the power and connecting to remote power strip.
5. Zeke has found a way to by-pass zapped APV card on J0 bottom. Trying to run J0 top, still causes crate to become unstable.
6. Beamline
1. David is looking at 'pedestal' values of BCM at different points in run when beam was off. This are converted to frequency by VtoF.
7. Replay analysis
1. Will look for LH2 elastic events to use them to understand BBCal and HCal responses.
2. Trying to calibrate momentum, using H-elastic at lower Q^2.