[Rgc] [New Logentry] RC Daily Summary - 3 November

[mckinnon at jlab.org]

Logentry Text:
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After yesterdays maintenaince day, beam permit was requested at around15:30

Around 16:30 the target polarisatoin dropped to 0% with ice on valve the suspected cause. The target experts took a rapid access and defrosted the valve.
17:30 MCC energised the tagger in preparation for return of beam

Beam to tagger dump at around 19:00 and harp scans taken.
Moller run taken at (ramped up to 10nA) with polarisation ~83%

Around 21:00 target experts had to take another rapid access to remove more ice on the valve
Works including replacing a couple of O-rings was undertaken and this took the remainder of the swing shift

01:00 target group work is done and beam permit requested

02:00 MCC having troubles to send us 8nA due to mid and down stream halo trips

06:00 MCC say the beam is fine but they can't get beyond 5nA
06:40 MCC requests that a 2H01 harp scan be done but this should not be done when we have the raster. If MCC request this again, tell them if they need to diagnose beam with a harp, we can offer them tagger 2C24 and follow the procedures required for that. 
Shift ended with no beam

08:30 MCC fixed our beam issue and delivered 4nA. Eugene begins beam tuning by reducing raster by 0.5V in both x and y. Increased to 8nA so raster size increased but it looked like we were hitting top of target so he tuned positions. Thanks Eugene. The new raster and beam positions have been updated to the wiki page and the white board.
10:14 run 17353 started with Pt=-66.5%, 8nA, HWP In

The plan for today is to take production data on NH3-. Initial thought was 2 days worth (today and tomorrow) but efficiency has been low so far due to the above. Let's discuss at RC meeting 2pm 

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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/4075843
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