Run Coordinator report: Fall 2021 w2

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I had the rare honor of being the RC to bring the beam into the Hall during the current run period, after the 5th pass separator issue was resolved. The first tune beam reached Hall D tagger at noon last Thursday (09/16/2021), CW was established three hours later. At this moment, JLab was under the three-hall operation with Hall D beam on Hall A slit. During the first set of the detector checkout, we quickly identified Active Collimator bias cable was not properly engaged, which caused beam time loss. In addition, the microphone installed in the counting-house was not suitable for smooth communication between the counting-house and remote shifter. These issues were resolved the following day with help from the experts.

From Friday to Monday, the CCAL crews and shifters completed the snake can to calibrate the Compton Calorimeter (three rounds of crystal-by-crystal scan). This was done mainly with the uncontrol bleedthrough beam from Hall C, during their 40-70 target and spectrometer calibration runs. The controlled bleedthrough was severe enough to generate a CCAL rate that is 2x larger than our own low current 2nA beam. Due to this unstable beam condition, the planned TAC run for three shifts was cut back to only 5 hours. Please note that this much-needed TAC run was due to a Hal C downtime for a magnet issue, they generously extended this downtime for one hour to allow us to complete the TAC run.

The planned Beryllium target change occurred on Tuesday from 7:30 am - 3:30 pm, by 4 pm we were back to beam permit. All this is due to great planning and coordination by Tim, execution by Techs, and support by Radcon, Survey and Alignment, and Target group.

We are currently in the production mode and accumulated almost 15M triggers of Beryllium target data, note that our run condition is 100-200nA on a 10-4 radiator. After a rocky start for the data monitoring system, it returned to the normal GlueX production standard.

There are a few outstanding issues worth mentioning: currently, the counting-house camera for the right whiteboard is still down, which should be fixed in the next few days. Accelerator experts have assembled a task force to look into the Hall D bleed-through issue from other halls, it is more important than ever for us to press the issue for potential improvement/solution.

To end my summary, I would like to give my special thanks to all remote shifters, they have been extremely helpful and patient, during the first week of running. They shared and completed the tasks together with the local shifters and contributed greatly to the run plan, despite the fact that they have to deal with connection and VNC related issues and network frustration from time to time. Really great job!