Run Coordinator report: fall 2022 w8

We started this week by taking data on the empty target at 200nA. By 7:45AM Thursday morning, we had collected 2.2B total triggers on the empty target which corresponds to roughly 31% of the photon flux since the previous filling of the target being spent on the empty target. Afterwards, the target was filled, and we resumed production at 200nA. During the day on Friday, there was a Wien angle change and a pass-change for Hall A which resulted in a downtime of about 7 hours. During this downtime, 5 FCAL bases were replaced, and a new calorimeter prototype was installed in the PS test setup. Production data resumed early swing shift after the usual harp scans were performed. Friday evening we collected 2, 2hour runs with 250nA beam current for studying the systematics associated with accidentals and detector pile up in the Compton scattering analysis. It was noted Saturday evening that the communication with the CAEN HV crate for TAGH Counters 1-120 had ceased. The HV was still being supplied, as evident by the scalers and monitoring histograms, and the decision was made to not make an access to reset this crate until Monday. At 7PM Saturday evening, a 2K cold box tripped in the NL. Experts had to be called in, and it took some time to recover, with the beam returning to Hall D at 3:30 AM Sunday morning. Another long downtime occurred Sunday during the day shift because of a smoke alarm in the collimator cave. After investigation by the Fire Department and the JLab Fire safety group, it was found that this alarm was caused by a short of the switch in the alarm control panel from the chilled water leak on the west wall of the hall. By early swing shift on Sunday we were back to production. It was noticed late Sunday night that the fADC module for one group of TAGM columns was dead. We continued running overnight without these fADC channels, and a controlled access was made to the tagger hall on Monday morning to replace this module. At the same time, the CAEN HV crate for the TAGH was reset, and communication was recovered. We resumed production on the helium target until Monday afternoon at 4:30PM, when the target was emptied. We continued collecting data at 200nA on the empty target until Tuesday morning when an issue occurred with the Arc 9 Box power supply. The beam was down for 17 hours because of this. The beam was restored 8PM Tuesday, and continued collecting data on the empty target until the accelerator was shut down for the scheduled ARW tour Wednesday morning.

In total we collected 9.8B triggers on the full target this week, and 0.87B triggers on the empty target data collected at the end of the week (~20% of the photon flux was on the empty target). The accelerator efficiency was about 53.4%, with close to 15 hours of BANU due primarily to the smoke alarm issue, the access to the tagger hall, and some DAQ crashes/overhead.