[Sbs] [New Logentry] RC Daily Summary - 09/30/23

[ojevons at jlab.org]

Logentry Text:
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I had naïvely thought that I could wait to write this until we had started to take production data, but alas it was not to be. The beam gods show no mercy. Amen.

Yesterday's DAY shift managed to start the beam recovery procedure, but was stopped every time they wanted to run on the C-hole due to Ion Chamber trips. MCC spent all of the rest of DAY (and further) trying to get this fixed. With the beam not being able to be delivered, Alex made an access to change one of the fADC modules on the HCAL. Once installed, he and Jiwan made sure the module was working, and it looks like it has solved the issues that HCAL was having.

The Ion Chamber issues continued into SWING shift, so MCC called their Optics on-call person, who spent the rest of SWING and half of OWL looking into the beam issues. In addition to the IC trips, MCC notified the CH of other faults that they were concerned about:
- One relating to the beam window cooling jets, which ended up causing FSD trips twice (https://logbooks.jlab.org/entry/4189513). These seem to have resolved themselves, but it is still worth keeping an eye on the flows to make sure that they don't get too erratic.
- Another relating to a setpoint readback issue in one of the Moller quads (https://logbooks.jlab.org/entry/4189495). MCC seemed to imply that this might have been causing some of the IC trips, so I spent some time on call to the Moller group (many thanks Faraz and Don for not being too angry with me disturbing you evenings!). By the time I got to the CH, MCC informed me that this readback issue seemed to have fixed itself, and it's not seemed to have happened again since.

At 4:30 am, the CH called me and told me that, after inquiring with MCC about the status of the beam, they had been told that the Optics expert had gone home, and that they would not be delivering beam to Hall A until the DAY shift. As such, I let the SL go and get some sleep, but the TO had to again stay to monitor alarms (my apologies, Hunter!). I called the MCC and asked when this decision had been made; they told me that it had been done at 4 am. Not only was the shift crew or RC informed of this decision at the time, but I do not think the PD had been told either. I raised this at the PD meeting this morning, and it has been noted.

Today's DAY shift started with a new Optics expert at the MCC to try to fix the beam issues. At 11:10 am, I got a call from the SL, informing me that MCC had been delivering 10uA beam to No Target (for tests), and wanted to test 35uA. This suggested that the beam was nearly ready to be recovered, and at 12:30 pm, I was informed that the CH was ready to take data on the production cell. The optimism for this has been short-lived, as a machine trip has happened which will stop the beam for at least an hour; we will go for beam recovery as soon as this is fixed. Fingers crossed, we should be looking to restart production by the start of SWING shift at the latest.

In related news, I want to thank Kate and Arun for stepping up to fill today's DAY (TO) shift at extremely short notice, and thank you to Eric for filling the open slot on the SWING shift. We are nearly fully staffed for the rest of my time as RC, however we are still missing a TO for both OWL and SWING shifts on Wednesday 4th. Please sign up for any open slots; the shift schedule can be found at https://misportal.jlab.org/mis/physics/shiftSchedule/?experimentRunId=SBS-GEn-2022.

On a more fun note, I have bought some British biscuits for the CH snack pile (Cadbury's Fingers and Jammy Dodgers, for those interested), and I have bought a box of proper tea bags for anyone to use. Enjoy!

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This is a plain text email for clients that cannot display HTML.  The full logentry can be found online at https://logbooks.jlab.org/entry/4189853
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