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    User name peter

    Log entry time 08:06:43 on December24,2003

    Entry number 115173

    keyword=Owl Shift Summary

    Owl Shift Summary

    SL: Peter Monaghan
    TO: Bryan Moffit

    00:00 Shift begins with Bodo continuing his HV scan on the RICH detector. Thick carbon foil target in use.

    00:30 RICH tripped - being reset. The HRS and Septum magnets have been reset to a momentum of 1.01 GeV/c in order to make coincidence measurements.

    00:50 Starting simultaneous beam heating studies and high rate RICH running (+ HV scans).

    01:15 MCC take the beam away to do an F-OPT test; estimate beam return in 30 minutes.

    01:49 MCC have finished their beam studies/tests and have delivered 15 uA beam to us. Starting another beam heating test run.

    02:13 RICH HV and septa temperatures seem stable. Now going to 30uA beam. RICH tripped as beam current ramped up to 30 uA; tripped at around 27 uA; reset HV to 1950/400 to test at 30uA.

    02:57 RICH HV and septa temperatures stable at 30uA. Now going to 45uA. RICH tripped as beam current increased. Reset HV to 1950/400 to test at 45 uA.

    03:06 RICH HV tripped off again shortly after reaching 1950/400 with a beam current of 45 uA. Try setting the HV to 1950/600 and see what happens.

    03:40 RICH HV stable for run #1589. Now going to 60 uA beam current. Robert Feuerbach has come in to work on tuning the HV settings for S2 in the right arm.

    04:30 The 'Target Flammable Gas Sensor' alarm has gone off. After paging Jack Segal, he explained that the channel giving the alarm was NOT connected to any sensor and so it was a bogus alarm. He suggested emailing Mike Seely and asking him to take a look at it, which I have done. Unfortunately, the alarm continues to sound, even if we press the 'accept reset' button.

    05:00 Runs 1590, 1591 and 1592 had stable RICH HV but the beam tripped off for longer periods before the septum magnets had reached a stable temperature.

    05:25 MCC called to explain they were having problems with their BLMs - beam away for a few minutes.

    05:35 MCC believe they have solved their problems and are now trying to ramp back up to 60 uA beam; meanwhile both septum magnets are cooling down again.

    06:04 MCC now deliver 60 uA beam back into the hall. We are continuing with run 1593. RICH HV still stable and septum magnets heating up again.

    06:39 Asked MCC for 75 uA. RICH HV stable at 75 uA.

    07:20 RICH HV tripped. Try resetting HV to 1950/600.

    07:30 Asked MCC for 90 uA. RICH HV stable (1950/600) with 90 uA beam current.

    08:00 RICH HV remained stable (1950/600) during the heating test with a beam current of 90 uA. As can be seen from the septum temperature strip charts (see Bryan Moffit's separate entry) there does appear to be noticable heating of the septum magnet coils with increasing beam current. MCC have taken beam away now for Christmas. Merry Christmas everyone!!

    Run Summary

    1584 RICH HV scan HV: 2050/400, T3 = 38kHz, right arm = 2.030
    1585 RICH DAQ crashed; junk test run to verify pedestals for RICH
    1586 Beam heating/RICH HV scan HV: 1950/400, T3 = 77 kHz, HRS = 1.01 GeV/c, beam current = 15 uA (short run)
    1587 Beam heating/RICH HV scan HV: 1950/400, T3 = 70 kHz, HRS = 1.01 GeV/c, beam current = 15 uA -> RICH HV stable.
    1588 Beam heating/RICH HV scan HV: 1950/400, T3 = 160 kHz, HRS = 1.01 Gev/c, beam current = 30 uA -> RICH HV stable.
    1589 Beam heating/RICH HV scan HV: 1950/600, T3 = 220 kHz, HRS = 1.01 GeV/c, beam current = 45 uA -> RICH HV stable.
    1590 Beam heating/RICH HV scan HV: 1950/600, T3 = 280 kHz, HRS = 1.01 GeV/c, beam current = 60 uA -> Beam trip before septum temperature stablised; RICH HV stable.
    1591 Beam heating/RICH HV scan HV: 1950/600, T3 = 300 kHz, HRS = 1.01 GeV/c, beam current = 60 uA -> Beam trip before septum temperature stablised; RICH HV stable.
    1592 Beam heating/RICH HV scan HV: 1950/600, T3 = 300 kHz, HRS = 1.01 GeV/c, beam current = 60 uA -> MCC having beam delivery problems; RICH HV stable.
    1593 HV tune on S2 in right arm (Robert Feuerbach) - Test run. RICH running with HV: 1950/600; beam current fluctuating as MCC ramp back up. Eventually run with 60uA beam and see stablised septum temperature.
    1594 Beam heating/RICH HV scan HV: 1950/600, T3 = 420 kHz, HRS = 1.01 GeV/c, beam current = 75 uA -> RICH HV tripped around same time that the run ended.
    1595 Beam heating/RICH HV scan HV: 1950/600, T3 = 450 kHz, HRS = 1.01 GeV/c, beam current = 90 uA -> RICH HV stable.