User name M. Rvachev
Log entry time 08:11:53 on December 21,1999
Entry number 31677
12:00 Waiting for beam (energy is being switched to nominal 4044 MeV)
1:15 EQ3 quenched for no reason; brought it back and cycled to 1600A.
3:15 Got beam
3:25 Started ep. ep energy measurement was not successful because of ep DAQ
problems (cannot write events to disk).
5:40 Tuning beam back to achromatic mode
6:15 MCC cannot deliver beam with absolute fast feedback in energy on. They can
start delivering with absolute FF and then switch to relative, which they claim has
the same effect as running all the time with absolute, provided that they "retune"
beam energy after every trip. After contacting Arun we agreed to run in this mode for the time being.
7:00Now MCC says that the tune with switching from absolute feedback to relative
(and preserving absolute energy value) is impossible, since they get trips with absolute mode.
7:10 Now it turns out that tonight's shift so far has been in ep beam tune.
7:30 MCC has some problems now.
7:40 Now we got achromatic tune, but no feedbacks. Taking data (1514).
1496-1500 junk (cosmics with beam on and off)
1501 - empty target run with stable 5uA current in ep mode - can be used to study background with beam on
1507 12C pointing run (raster off) (ep tune)
1508-1509 raster check
Start He3 elastic normalization runs (beam in ep tune):
1510 He3 elastic, raster 4*4 at MCC (we see it as dx=6mm, dy=4mm at supposedly
badly calibrated spot++), beam 5uA, lost beam in the end of run
1511 -''-, lost beam in the end, good run
1513 He3 elastic, raster 4*4, 5uA, good run, a few trips during run
Start achromatic tune runs. All feedbacks are off.
1514 He3 elastic, 5uA, good run
1515 He3 elastic, 5uA, good run (trip in the end)
1516 He3 elastic, 5uA