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User name A. Puckett
Log entry time 00:02:32 on January21,2009
Entry number 257059
keyword=Swing Shift Summary, 1/20/09
Hall was in controlled access when we took over from day shift. MCC called early on, was ready to send the beam, we waited a few more minutes for everyone to leave the hall. Went through the usual procedure of checking the beam position on BeO at 2 uA, then checking the trigger rates and spot++ size for 3x4 and 6x6.6 raster sizes at 2 uA on 3He. At the larger raster size, it looked like there could be some minor scraping toward the beam left side of the target, so we moved BPMA+B to less negative values in their X coordinates by about .5 mm each and then verified with a spot++ that they had moved in the desired direction and there was no longer any spike in the raster current distribution. Note that there was never any scraping evident using the nominal raster size, only with the large raster size. It was not until about one hour into production data taking that we started playing around with the beam positions. The new BPM positions are:
BPMA (X,Y) = (-1.0, 2.2)
BPMB (X,Y) = (-0.4, 2.2)
This decision was made by the experts in the back room, not the shift crew. I will instruct the night shift to stay with these beam positions, but the experts may wish to discuss it further.
Finally, this shift was characterized by a higher-than-usual occurence of HV trips, including three trips of the BigBite wire chambers and even one trip of the left arm VDCs.
Production run summary:
Run #, charge, comments
5382, .004965
5383, .03954
5391, .04984
5392, .02088
5393, .04993
5394, .02161
5395,