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User name paschke
Log entry time 00:12:28 on April20,2004
Entry number 118628
keyword=swing shift summary
16:00 Shift starts with no beam, recovering from "CD0 festivies"
17:10 Beam returns. BPM 4a (1.9,0.2), 4b(-1.9,-1.5)
FFB on.
started run 2558. Nominally "junk", as beam just came on, but
actually beam looks pretty good (couple of trips, current changing).
17:25 90 uA, production starts.
18:30 ep power supplies turned on, waiting to stabalize.
18:42 moved to 10cm optics target. Started Doug's optics program, changed
prescales T1=4, T3=1, beam about 5 uA.
Z-E. worries about deadtime, figured we should prescale more. Started
run 2562, with T1=8, T3=2. roughly 16% dead.
19:00 moved to 24cm optics target
19:05 Arne called: he will start energy spread measurement and OTR/SLI cross-calibration
expected: 1 hour. Turned off ep detectors to avoid damage. Beamline HV in ep system
tripped, so those channels were turned off as well.
20:05 Arne called: energy spread is bad, expert on the way. Until expert arrives, we
returned to the optics runs.
22:05 Energy spread appears to be good, measured by OTR to be <3e-3. This is true only
at high current, so no harp scan was done to verify setpoints.
22:10 Jay Benesch trying some new quad values for Hall A to try to reduce trip
rate.
22:25 MCC called. They're ready to try the new quad settings. They remeasured
OTR width with new setpoints to verify energy width was unchanged: ELog entry.
22:45 Lots of trips, no win. MCC is trying to find the upper limit for current.
Jaideep points out that we have pulsed beam... at 33 milliHertz.
23:20 Trip rate still high...