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User name miham
Log entry time 08:03:16 on November24,2010
Entry number 341480
keyword=Owl Shift Summary (11/24/10)
Swing shift summary: Miha Mihovilovic (SL), Lamiaa El Fassi (TO)
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EVENTS
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00:00 Shift started normally. We inherited run #8979 from swing
shift. We are taking production data on LH2 target.
00:36 We noticed that DVCS calorimeter ADC current monitor is
frozen. We are going to reboot IOC, but first need to
wait run #8979 to finish.
00:40 Compton is working strangley. Photon rate has high background.
We did another coda reboot after run #24221, but did not
help. For the time being, we will leave it as it is.
01:00 Between runs #8979 and #8980 we rebooted DVCS calorimeter
IOC as instructed on wiki. We had to do it twice. Now
readback monitor works well again.
01:39 In the last hour beam current was 2.8uA instead of
requested 3.0. I called MCC and asked them, if they can
increase current to 3.0. They have tried but after first beam
trip, current went back to 2.8uA.
02:44 MCC has problems keeping our beam current stable. Every
change in Hall-C currect affects our beam current. When they
took beam away from HallC, our current increased for
approx. 0.5uA.
03:12 We have noticed that photon rate signal was much better when
current in HallC was < 100uA. Once they increased it back to
150uA (at -15minutes) a large noise in compton signal
returned.
04:32 I have added HallC beam current to Compton strip charts
(lite green line). It shows that photon rate directly
depends of HallC current. Higher the current, more noise
is in the Comton signal.
06:49 Beam current was again lower than 3.0uA. It was 2.8uA. It
had been so for last hour. Therefore we called MCC again and
asked them if they could adjust beam current once more to
3.0uA. At least for now, beam current is better (3.1uA).
08:00 Shift ended in production mode during runs #8986 and
#24234.
RUN LIST
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Run Events BCM U3 D3 (C) Time Avg Curr Deadtime
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8979 275 k 0.00890 0.00984 59.5 mins 2.6249 uA 6.62%
8980 290 k 0.00959 0.01061 59.5 mins 2.8274 uA 6.45%
8981 314 k 0.01049 0.01156 61.9 mins 2.9708 uA 6.56%
8982 End-of-run file is missing
8983 302 k 0.01005 0.01106 60.6 mins 2.9048 uA 6.51%
8984 290 k 0.00951 0.01053 61.1 mins 2.7313 uA 6.07%
8985 264 k 0.00846 0.00935 58.1 mins 2.5543 uA 6.30%
8986* Passed to next shift!
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* Look for notes abouts these runs in the time table.
COMPTON RUN LIST
===================================================================
Run Events START STOP
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24221 N/A 23:56 00:40
24222 2.5M 00:46 01:30
24223 1.8M 01:31 02:03
24224 1.7M 02:05 02:35
24225 1.7M 02:36 03:07
24226 1.9M 03:09 03:43
24227 2.0M 03:44 04:20
24228 2.0M 04:20 04:56
24229 1.7M 04:57 05:27
24230 1.7M 05:28 05:58
24231 1.8M 05:59 06:31
24232 1.9M 06:32 07:04
24233 1.7M 07:05 07:35
24234 Passed to next shift