[Halla_running] [New Logentry] Hall A status and no RC meetinig today

[sanghwa at jlab.org]

Logentry Text:
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Yesterday, we tried to do Moller measurement yesterday evening was not able to do the measurement due to the target magnet quench (https://logbooks.jlab.org/entry/4179897).
After backing out from Moller, we restored the CW beam for physics data taking. Dedicated Carbon hole runs (1M events) were taken with reduced raster size, and we are more confident about the center position (https://logbooks.jlab.org/entry/4180189). Target experts confirmed that we have the carbon hole target with 1mm hole diameter, and this is something we should discuss after the weeked. 

During the owl shift, we successfully brought CW beam to the PolHe3 target, following the slow ramping procedure (5->10->20->30uA). The IC rates for He3 were comparable to the Reference cell with N2. BBCal trigger rates were higher compared to before, and here is the current threshold values we set: https://logbooks.jlab.org/entry/4180257. And, yes, we are in PRODUCTION data taking!
We are taking 30uA, with 10% reduced raster size. Operation restrictions have been updated accordingly.
Replay plots are posted to the logbook and shifters are updating the run sheet, so please take a closer look at the data. From the last measurement, the target polarization is 41.5%. 

We will not meet for the RC meeting today, but continue taking the production data over the weekend. 

Reminder for shifters:
- Beam recovery procedure update: https://sbs.jlab.org/wiki/index.php/HOW_TOs#Beam_Recovery_Procedure
- https://sbs.jlab.org/wiki/index.php/HOW_TOs#What_to_monitor_during_production_running_on_glass_cells
- Log the runs we are taking (Go to GEn runs spreadsheets on Wiki page: https://sbs.jlab.org/wiki/index.php/Main_Page)
- TO: there is additional monitor screen (vnc) for the two new lasers. If the laser goes off, you will see the current drops --> call the expert.
- For any access entering the Hall A, check list form needs to be filled out (https://sbs.jlab.org/wiki/index.php/RC_meeting_and_Run_Plan,_Friday_Sept._15,_2023#Procedures)


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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/4180434
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