[Hallc_running] [New Logentry] RC update, Feb. 26, 2024

[sanghwa at jlab.org]

Logentry Text:
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We started the Day shift yesterday with an access to address the LV issues of column 24 and 25. Julie, Josh and Hao went to the hall and replaced the PMT and base that was causing the problem (https://logbooks.jlab.org/entry/4256617). Later they found unstable LVs for additional columns and fixed the issue with an escorted access (https://logbooks.jlab.org/entry/4256646). 

During the access we also found that the temperatures in the SHMS huts elevated. It turned out that the AC unit is coupled to the LCW sysytem, and when the LCW went down on Saturday it tripped off the AC unit as well. Facilities came in and reset the AC unit (https://logbooks.jlab.org/entry/4256636) which solved the problem. We also realized that the crate temperatures in the SHMS hut are not monitored. Bill Henry is working on adding them in Munin. 

After that we came back to beam permit and resumed the data taking around 2pm with Dummy target. We switched to LD2 target around 6:30pm and increased the current to 8uA (https://logbooks.jlab.org/entry/4256787). It has been relatively smooth production running since then. We completed one cycle of the data taking for this kinematics at the new calorimeter position (6m). We are taking the second cycle of LH2 data now. 

We will continue the production running until around 11am today. We will then turn off the NPS calorimeter and do DIS singles scan (~2h). After that we will do the BCM calibrations which include the Faraday cup measurements. This will take about 2h. Once all the special tests are done we will go back to the production running. See the run plan for details: https://hallcweb.jlab.org/wiki/index.php/Short_Term_Run-Plan


Other notes/issues:
- Data has different patterns from before: https://logbooks.jlab.org/entry/4256593, Wassim updated pedestals, looks better now. 
- Reported current consistently lower than requested, re-homing the Hall C laser fixed the issue: https://logbooks.jlab.org/entry/4256774
- One NPS calo channel (raw 34, column 25) seems dead: https://logbooks.jlab.org/entry/4256803


We will meet at 11am for a daily meeting, 2nd floor conference room at CH.
Zoom connection link:
https://jlab-org.zoomgov.com/j/1617015555?pwd=L09IQ216dml6ZmM5ODExVjFsMX
Meeting ID: 161 701 5555
Passcode: 288953


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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/4257065
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