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    User name Calarco

    Log entry time 16:11:17 on February 7,2000

    Entry number 33045

    keyword=Shift Summary

    08:01 Ended run 1970. Asked for access to change HRSh to 12.78 deg for
    kinematics point #25. Started momentum change to P_p=2.229 GeV.
    Recycled Q2 and Q3
    08:30 HRSh angle set to 12.80 deg. Momentum set to 2.229 GeV.
    08:50 Beam on, checked spot at 5 microA, increased raster settings to 4.8X4.8.
    Set prescale factors to obtain T1=T2=T3=T4=100Hz, PS5=1. Checked
    OTR at 50 microA and removed. Now running run 1973 with 94 microA
    at kinematics #25.
    09:35 DAQ stuck, ROC1, ROC2, ROC3, TS0, TS1 and ROC14 not responding.
    Had to kill CODA. No Endrun for run 1973. Rebooted ROCs and CODA
    10:05 Noted a double peak in the hadron S1 TDCs. This is most likely due to
    the fact that there seems to be a high background rate in the hadron arm
    as evidenced by the fact that the scaler rates for T3 and T4 are about equal.
    If S1 is hit and S2 is not, then a T4 is generated with a time which is shifted
    from the "good" timing because the S1 strobe is delayed after the S2 strobe.
    10:20 MCC has just informed us that we have lost fast feedback. We can still run.
    They are investigating.
    10:20 An analysis of run 1973 shows that out of 600,000 events (coming in at 300
    Hz) we get a total of 5,000 coincidences (0.8%) of which 150 are trues and
    the rest are accidentals. Of the 150 trues, about 50 have E_miss indicating
    2bbu. This would indicate that the goal of 500 2bbu events in less than 10
    hours. I calculate from this that the trues rate of 2bbu events is 90/hr.
    This will give 540 events in the 2bbu peak in 6 hours, not 26.
    10:25 Bob Michaels took a look at the data with hana. The high T4 rate is really
    junk ... few look like they should be T3. Probably due to high background
    at this very forward HRSh angle. A similar analysis of earlier runs berfore
    the angle change gives a T4 rate only about 20% of the T3 rate.
    10:37 Fast feedback back on.
    10:40 Ended run 1974. Will lower current to 40 microA and do OTR check. Looks
    OK. See OTR entry. FWHM was about 120X150 micron^2.
    11:00 Back on the air with run 1975.
    12:05 Run 1975 ended at 12:02. Put OTR in at lower current for a check. FWHM
    same as before. Grabbed OTR screen to halog. High current returned and
    run 1976 started at 12:08.
    13:07 Ended run 1976. Cecked OTR again. Looks OK. Same widths as above.
    Started run 1977 at 13:13.
    13:40 MCC reporting problems with PSS. We have lost beam for a while.
    14:10 MCC reports that we will be down 3-4 hours MINIMUM. I knew this shift
    was going too smoothly!!
    15:31 After unsucessfully trying to start a pedestal run, we finally contacted Bob M.
    who told us it was broken. We are now taking a cosmics run 1979 until such
    time as the beam returns.