[Sbs] [New Logentry] Hall A RC Update April 1, 2025

[ole at jlab.org]

Logentry Text:
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The magnet controls problem discovered in the accelerator was fixed during the day shift yesterday. A few power supplies were apparently misprogrammed and responded to commands intended for other supplies, so the last two weeks of tuning were like flying an airplane and discovering mid-flight that rudder controls actually move wing flaps. The machine setup had to completely redone after that, which is still ongoing, but progressing very well. Accelerator was very happy about the machine performance and sounded optimistic about beam delivery at the morning meeting. Barring emergent issues, beam may be in Hall C within the next 12–24 hours.

The official physics beam time started with yesterday's swing shift and will run for 20 weeks, unless extended, as dictated by budget numbers.

Once Hall C has acceptable beam, the other halls will be brought up in a staggered fashion, with Hall A last, 5 days after Hall C reports acceptable beam. This puts the Hall A startup to Monday, 4/7. Hall A shifts remain cancelled through Thursday Owl, with further delay likely. Please plan accordingly.

We continue to be plagued by a small vacuum leak on the downstream side of the target. A seal was replaced yesterday, which seemed to help, but did not completely fix the problem. The tech crew continues to work on it as I write.

Aside from the leak, progress in the hall has been very good. Ion chambers and the SBS corrector magnets were checked out and approved. A survey of the SBS magnet is planned for this morning. After that, aside from the leak, I understand that we are ready for doing the final beam checklist.

Some detector and DAQ debugging is ongoing. All the major pieces of the analysis software are in place. Online calibration, analysis, and monitoring software is being configured.

We are in need of a detailed run plan. PIs are aware. This should be in place in the next few days.

We will have the RC meeting today at 3:30 pm in the meeting room on the 2nd floor of the Counting House and via Zoom:
https://jlab-org.zoomgov.com/j/1616220064
Meeting ID: 161 622 0064
Pass code: 314159
Wiki page: https://sbs.jlab.org/wiki/index.php?title=RC_meeting_and_Run_Plan,_Tuesday,_April_1st&action=edit&redlink=1

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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/4346379
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