[Halla_running] [New Logentry] RC report, plan and meeting

[ciprian at jlab.org]

Logentry Text:
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After getting reasonable background rates for the Compton (~6 kHz on the DS counters) we proceeded to run production. We observed that the Compton Photon Detector rate was unstable and that was linked to periods of time when the Fast FeedBack (FFB) system was on (https://logbooks.jlab.org/entry/3826709). This was a continuation of the issues we had in the previous days with excess vertical noise jitter that seemed to be caused by the FFB system. 

We ran a test in the afternoon where we tried different configuration of the FFB system:
1. FFB on (RF on), FeedForward (FF) on, FF DAC on: run 7699 
2. FFB on (RF on), FeedForward (FF) off, FF DAC off: run 7700. This produced significant Ion Chamber trips due to beam instability and we could only take data for 15 min.  
Both of these cases are summarized in Tao's log entry: https://logbooks.jlab.org/entry/3826840 With FF off and FF DAC off we could not control the energy vernier for beam modulation. We decided to run with everything off. 

Cameron and Amali took a PITA scan and pedestal scans: https://logbooks.jlab.org/entry/3827134

Over night we ran with the FFB system (including FF and FF DAC off). The data quality looked good and we saw increased stability in the Compton Detector rate (https://logbooks.jlab.org/entry/3826851). 

In the morning we have asked MCC to continue tuning the beam to produce lower rates for the Compton chicane (in Feb we had ~2kHz on the DS counters). After about two hours we will continue production into the weekend (with the entire FFB system off).

We will have our regular RC meeting today at 3 30. Bluejeans: 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/3827301
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