Run Coordinator report: Fall 2021 w12

Run Coordinator Report for November 4 - November 10, 2021

In this week, we completed the run period 2021-08 for the PrimEx-eta experiment (E12-10-011) and commissioned the SRC/CT experiment in Hall D. We were scheduled for 88h of running and we received beam for 48.8h (55.5%). We used the beam for 45.8h, the minor down time was caused by an access to the tagger hall to reset 2 controllers for the goniometer, which required RadCon survey, and another access to the experimental hall to reset unresponsive VME crates. We used 100% of the scheduled experiment hours and collected 90% of the total experiment data. The beam energy during this run period was lower than initially requested in the proposal, which resulted in a lower figure of merit for the PrimEx-eta experiment.

We started this week with an accelerator maintenance day on November 3rd, during which we replace 15 FCal bases. The beam was finally restored around 11pm, but several interruptions prevented us from stable data taking. Only at 2pm the following day, we could resume production running until Friday 8am, when the beam was taken away for a beam energy change. This was the end of the PrimEx-eta experiment in Hall D for this year. We used about 1h of the beam for Trigger studies for the upcoming SRC/CT experiment with different beam currents.

During the accelerator reconfiguration, we performed a Safety Walkthrough, installed new equipment in the test area behind the PS and switched the DAQ and monitoring setup to the new run period 2021-11. This counting house was not staffed between Friday 10am and Sunday 4pm. During this time, the vacuum in coil 4 of the solenoid degraded, which lead to a dump before the auxiliary pump could be turned on. The vacuum quickly recovered afterwards, and we could already start ramping up the solenoid to 800A on Saturday. It was fully restored on Sunday afternoon, effectively causing no down time on our side.