[Halla_running] [New Logentry] RC daily summary

[jonesdc at jlab.org]

Logentry Text:
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Yesterday (Weds) was a maintenance day. The hall was in Controlled Access starting shortly before 9AM. Around 3PM the techs unlocked the SBS power supply and we were ready for beam. Beam, however, did not arrive until the end of swing shift. Power glitches took down many elements in the North Linac and the injector would no longer transport and had to be retuned. After tuning beam for a couple of hours, we finally had a beam profile that worked and around 1PM started beam centering.

The ECal team huddled and decided to implement a quick and dirty approximate calibration row-wise calibration to try to get closer to a flat E/p distribution across ECal. This was implemented increasing the gains by 20%-70%. It was expected to have a large effect on the trigger rate , so it was decided to raise the threshold to 50% and drop the current to 10uA for about 4 hours to get sufficient data to see the effects.
By the end of the owl we had collected about 4 hours of data amounting to only 0.12C. The trigger rate increased to 4kHz while the live time surprisingly stayed above 90%. Andrew is replaying this now and the results will take about 12 hours to start arriving.

Beam studies are going on during day shift today testing the use of the Conpton polarimeter  chicane in Hall A. It is expected to be done around 4PM.

The plan when we come back is to increase the ECal threshold to 60% and then increase the current to as high as we can while keeping dead time below 10%. 

We will have our regular RC meeting today at 1pm, Donald Jones will take over the RC from today.

Since yesterday's Day to today's owl:
* Total Accumulated Charge at Kin3 so far: 76.85 C (Goal: 100 C)
* Total Accumulated Charge at Kin3 since yesterday : 0.16 C

Updates from MCC:
* Hall A Compton study on Today

Current Issues and Hall activities:
* ECal calibration constant and Trigger threshold

Shift Summary:
* Yesterday's Day: https://logbooks.jlab.org/entry/4436164
* Yesterday's Swing: https://logbooks.jlab.org/entry/4436368
* Today's Owl:https://logbooks.jlab.org/entry/4436546

RC Meeting:
* We will have RC meeting today at 1 pm in the conference room in the second floor of the CH and on Zoom.
* https://jlab-org.zoomgov.com/j/1616220064
* Meeting ID: 161 622 0064
* Passcode: 314159

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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/4436900
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