Revision as of 18:16, 21 January 2023

Monday January 23

Past 72 hours

• Beam was off from Friday 7:30am to Saturday 2am due to vacuum issue in south linac.
• Saturday: Ran on amorphous (goni), 300 nA.

Shift Reports

• Day shift summary Friday, Saturday, [Sunday]
• Swing shift summary Friday, [Saturday], [Sunday]
• Owl shift summary Saturday, [Sunday], [Monday]
• Early Riser shift summary Saturday, [Sunday], [Monday]

Reports

• Empty target vertex reconstruction (Simon Taylor)
• TAGM timing plots (Richard Jones)
• DIRC LED performance (Bill)
• FCAL occupancy plots (Churaman)
• Harp scan Saturday morning. Convergence does not look very good, but we decided to run this way for now (amorphous runs).
• cdc currents (Beni)
• []

Issues

• RC volunteers needed (Beni's RC week because of his surgery, and Susan's week because she had to cancel her trip to the US). Hovanes and Simon volunteered to cover the two weeks.
• Numerous pressure alarms. Sensor problem? Since Saturday morning, instruction from Lubomir are that we should only acknowledge the alarms. No need for stoping the ongoing run. See also here. The suspicious sensor has been removed from the alarm (Hovanes)
• Beam energy oscillation investigation: Several accelerator experts are looking at it. No consensus whether it is real or not. Since it is at the MeV level, it should not be an issue for GlueX.
• 30% increase in rates compared to Summer 2020 run period.
  • Yields after BCM recalibration (A. Deur)
• Target control issue.
  • Target communication lost around 1pm Friday. Alarm acknowledged by shift crew without action or calling expert. New shift noticed this and called Hovanes. Hovanes informed Alexandre who checked what was the issue and call then Chris Carlin. Chris C. could not come (catching a flight at the airport) but instructed the crew to switch the the back-up IOC, which apparently fixed the issue. However, the controlled came back in a confused state (Full but with heater on, an incompatible situation) so Alexandre informed Chris Keith who went in (beam was off for repair during the whole event) with the shift leader (Dene) and partly fixed the issue by switching the target to local control.
  • We can monitor the target, but not control it remotely (switch empty <=> full). For the moment, this is not a crucial problem.

Plans

Friday January 20

Past 24 hours

• Ran on amorphous radiator (250 nA) until 10am. Then, beam was taken away for RF work (high current push for Halls A and C). Beam came back around 5:30pm. We did harp scans, a BCM/FCup calibration, and then ran on various amorphous radiators during the night and early morning. ABU= 11.5h for the day
• Several accesses done during the day:
  • Sasha (FADC replacement for TOF)
  • Sergey

Shift Reports

• Day shift summary
• Swing shift summary
• Owl shift summary
• Early Riser shift summary

Reports

• Harp scans. Sigma_y is too wide=> too wide photon beam spot (magenta). Okay for now (unpolarized beam)?
• TOF calibration (Beni), FADC replacement for TOF (A. Somov)
• Difference in Shape of Reconstructed photon beam energy with different AMO radiators (Churamani Paudel)

Issues

• Beam energy oscillation investigation (M. Tiefenback). Summary: Mike T. suspects the oscilations are not real but he is asking confirmation/advice from the system experts.
• Tim W. reminder on acknowledging alarms
• HVB currents look high and follow-up (Naomi)
• 30% increase in rates compared to Summer 2020 run period.
  • Original finding by A. Somov
  • Comparison of 2020 and 2023 for TAGH rates (A. Deur)
  • Check that TAGH counters scale with (A. Deur)
  • rho and pi0 yields (A. Austregesilo)
  • BCM/FCup calibration suggested by the PD, its results and follow-up.
  • the rate discrepancy after BCM/FCup calibration has been reduced by half (A. Deur)
  • Ran overnight on different amo radiators

Plans

• Thursday evening and Friday night:
  • Once beam come back, do Harp scans.
  • FCup test of our beam dump BCM.
  • Run 1h on the amo radiator of the goni (baseline for next runs below). 250 nA
  • Run 2h on 0.19E-4 RL amo radiator on radiator ladder (250 nA).
  • Run 2h on 1.12E-4 RL amo radiator on radiator ladder (250 nA).
  • Run (until the beam is taken away in the morning) on 3.4E-4 RL amo radiator on radiator ladder (250 nA).
• Beam off starting Friday morning around 7:30am to fix vacuum issue in south linac, until 4pm(?).
• When the beam comes back:
  • Harp scans
  • Production on goni amo radiator at 300 nA until Sunday morning.
• Hall access:
  • Sergey F.
• Diamond alignment: Sunday morning, ~9am.
• Until then production on amorphous.
• Link to runplan

Thursday January 19

Past 24 hours

• Ran on empty target until 7:20am. Then, beam was taken away for beam and RF study and acceptable beam came back only Thursday at 1:10am. ABU= 4h for the day
• refilled the target around 4:15pm.
• Several accesses done during the day:
  • Scot
  • Sergey
  • David Lawrence
  • Cody
• Took amorphous data, starting around 1:10am after aborted attempt to check diamond alignment.

Shift Reports

• Day shift summary
• Swing shift summary
• Owl shift summary
• Early Riser shift summary

Reports

• Harp scans (just our harp)
• Hovanes attempted to start diamond alignment between 10:50pm-1am. Not able to start due to lack of good beam.

Issues

• TOF rate issues (Beni)
• beam energy oscillation
• 30% increase in transmission compared to Summer 2020 run.

Plans

• Beam off starting around 10am for RF study, nominally until 4pm+/-4h.
• Hall in controlled access?
• Diamond alignment: Friday day ? (Hovanes unavailable today)
• Until Friday day, production on amorphous?
• Link to runplan