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    User name markowitz

    Log entry time 08:06:25 on February 6,2000

    Entry number 32880

    keyword=shift summary

    started shift doing

    3He(e,e'p) at theta_e=16.46 degrees, Pe=2.2029, theta_h=38.30 degrees, Ph=1.2950
    Had daq problems carried over from last shift: coda not running, ROC 14 errors. We tried rebooting several times, then paged Bob Michaels. He did not respond, but int he meantime coda started letting us take data (the roc 14 errors still occur, but usualy communication seems to re-establish itself after a short period of several minutes).

    01:05 mcc called. They lost a box power supply and beam will be gone 5-10 minutes.
    01:15 mcc called back. The problem is a hard failure requiring experts to be called in. The present estimate is an hour before beam is back.
    01:50 beam is being steered back into the hall.
    01:55 started taking data (beam back, raster on, spot centered,good otr).

    02:25 run 1911 roc 14 stopped responding at the end and we had to reboot roc 14. Lost 5 minutes.

    03:34 again daq troubles -- this time roc14 complains of spurious interupts. We are seeing an event size that is slightly large (about 3 kb/event). We reboot and the event size is about 1.5 Kb/event. Daq behaves itself. But according to Bob's deadtime web page, the event size should only be about 1 kb/event;. We do not read the fpp (I confirmed that the hv is still off) so perhaps something is "noisy" like a wire chamber? when I look at the tracks and hits and multiplicity in the wc, all looks fine.
    04:10 again, roc 14 stops responding. We reboot daq.
    04:50 changed to 10 cm dummy target, turned off raster, asked for 5 mikes max,
    reduced prescalers by a factor of ten. Started run 1924. MCC had to take
    OUT filter on OTR (due to drop in current to 5mikes)
    05:00 changed to the 15 cm dummy cell. started run 1925. Notice that event size is a bit smaller, about 1.1 Kb/evt with the dumy cells (event rate is also smaller, 1KHz).
    05:10 changed to 4 cm dummy cell. started run 1926. ROC 14 decides to die, along with ROC 1,2,3. Rebooted and started run 1927 (still 4 cm dummy)
    05:25 changed to carbon target, dialed up current to 20 mikes due to low rates.
    05:35 change spectometer settings: Pe=2585, theta_e stays at 16.46, Ph=0.848, theta_h=55.0. Cycle electron quads (since we go up) by hand.

    06:24 starting 12C(e,e'p) at new kinematics. Forgot to change the trigger timing.
    06:35 changed coincidence trigger timing. Runs 1929 and 1930 had the old trigger timing and were therefore mostly singles. 1931 and on have the correct timing.