[Halla_running] [New Logentry] Status update

[sanghwa at jlab.org]

Logentry Text:
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The chamber vacuum remains the same around few E-4 torr (and quite noisy readback) over night. This morning the target experts started looking at the target chamber vacuum issue again and found a problem that seems related to the watercell target. For those who had difficulties to follow the issue we have, here is a brief summary and the current status.

- Target chamber vacuum suddenly increased to 4-5.E-5 during the owl shift Saturday (https://logbooks.jlab.org/entry/3696333)
- A leak found around CF flange at base of turbo (https://logbooks.jlab.org/entry/3696480)
- Part replaced with a new spare but the chamber vacuum did not improve (stayed flat over night)
- Problem found from the watercell target, further details and plan are being discussed 

While the target group is working on the issue in the hall, injector group is addressing the beam loss and our expert is checking the parity quality together. Today's beam studies are planned for 4 hours since the originally planned 8h beam studies has been splited into today and tomorrow for Hall C spectrometer configuration change before their pass change. 

We will post further update on the status to HALOG once it's available. 

Shift infomation
- Day and Swing shifts are on standby. Shifters will be contacted once we finalize our plan for tonight. Stay tuned.
- We are mostly covered this week, but there is owl SL missing on Thursday. Please sign up if you can!
https://misportal.jlab.org/mis/apps/physics/shiftSchedule/index.cfm?experimentRunId=PREX/CREX
- Shift instruction from Wiki: https://prex.jlab.org/wiki/index.php/Information_for_Shift_Takers

Other work performed in the hall:
- Dustin and Devi worked on SAMs early morning. See Devi's summary: https://logbooks.jlab.org/entry/3697172

As a reminder, we will have a daily RC meeting at 3:30 (2nd floor CH meeting room) and discuss our plan. 
Bluejeans Meeting ID: 256 205 934 (Direct link: https://bluejeans.com/256205934)


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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/3697208
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