Commissioning and running of sPHENIX

[Stefan Bathe <stefan.bathe AT baruch.cuny.edu>]

Minutes shift change 2023-05-09

general
—————

power shutdowns

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- this morning at 9:00am C-AD electricians flipped the breaker of the chiller platform without checking with the shift leader to make sure the experiment is in a safe state, which it was not

- then we shut down power to the carriage in a controlled way

- all this is for inspections for the safety approval

- currently power is back on for all racks powered by the West transformer (feeding racks for all subsystems but TPC and sEPD)

  - we are turning those subsystem power back on also

- power is still off for all racks powered by the East transformer (TPC, sEPD) as the work done on the transformer didn’t pass inspection

  - the work is fixed right now, and we hope to turn power on later today

from Time and Planning Meetings (Tuesday afternoon C-AD meetings)

----

- Thursday evening (May 11):  first beam

- Monday evening/Tuesday owl (May 15/16):  beam vacuum scrubbing (turn off silicon detectors)

- Tuesday night (May 16):  first store for STAR

- Wednesday morning (May 17):  sPHENIX commissioning begins (first collisions in sPHENIX)

- daytime access through Friday, then will lose regular access
  - first full 8-h maintenance day June 14

Plan of the Day

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- make things work as well as they did before the power shutdown

evening:  Xuan

- opened plug door at 4:30pm and switched to restricted access

- TPC, EMCal, MVTX work

- several audio alarms:  emcal NW chiller alarm, communication issue

- GTM firmware update and reboot

night:  Brennan
- quiet night on restricted access- handful of self-clearing chiller alarms

day:  Ben

- see general update above

- restricted access

- scattered alarms, nothing noteworthy

- detector operator computers froze, had to restart, didn’t have password

- instructions to reopen GUIs need to be updated

MBD (Abdul)
- GTM update

- Mickey replaced two boards N49 to N64 to get the right gain

- tried to read out with laser, problem with DAQ, talked to Martin

- MBD FEM rack

HCal (Virginia)
- were taking cosmics last night

  - bias voltage in one of channels dipping low

    - will probably have to live with these fluctuations
- one half-high signal channel in oHCal:  needs cable wiggling, first attempt didn’t work

- need to replace clockmaster that had been taken out for repair

- TP board needs to be swapped

- same problems with data getting stuck at particular event, Martin investigating

EMCal (Sean)

- last night tracking down groups with problematic bias channels

TPOT (Hugo)

- nothing new

TPC (Takao)

- Jin did throughput test, completed

- now moving on to improving buffering throughput

- new noise source, identified last Friday, tried pulser cable, no effect

  - sectors 9,1,11 affected

INTT (Raul)  

- rc_daq tests yesterday; Martin:  new firmware version coming? yes

MVTX (Cameron): 

- found Friday that MVTX LV no longer turned on; this morning:  isolated to mainframe, now can turn on again, still blinking light, in touch with CAEN

- chiller platfrom :  airlock

- investigated stave we couldn’t communicate with

  - signal cables:  one pin bent:  no control line, looks like fixed, but using spare cable anyway

  - when power back:  will confirm communication

John:  additional sag in MVTX?  Cameron will take one more look tomorrow with Jimmy

sEPD (Chris P, Eric, John H)

- SEPD cables:   

  - fiber cables run, interlock cables and power cables to be run—>should be done this week (will lose access)

  - signal cables from one rack to the other?  no, instead move cables

DAQ (Martin)

- quiet day:  cleaned up in racks

ZDC (John H)

- racks now unlocked, should turn them on

gas/cooling (from Rob)

- fall-out from today’s power shutdown:

  - TPC is good again

  - MVTX has one air locked channel

- 
---------------------------------------------------------------------------------
Stefan Bathe
Professor of Physics
Baruch College, CUNY
and RIKEN Visiting Scientist

Baruch:                                     BNL:
17 Lexington Ave                      Bldg. 510
office 940                                  office 2-229
phone 646-660-6272                phone 631-344-8490
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