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2015/10/28 (Wednesday)

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Current setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55/33/50.
Overnight: Taking Cf data. Last flash at 8:11. Tower temp stable between flashes.
0915 Tower/MC(H35)/MC sensor/Cold Plate = 31.1/27.0/41.4/153 mK, Still = 1.30 K / 0.11 mbar, G1/G2 = 125/135 mbar, 1K Pot = 1.69 K / 13 mbar, Main bath = 37.8%
0920 Fill LN2 cold trap Dewar.
G2 up relative to G1. Is a trap impedance forming? It has been rising since about 2am.
0925 Put Soudan Cf source back in safe.
We started this run circulating through LN cold trap 1 then switched on 2015/09/28 to cold trap 2. We never cleaned out Cold Trap 1 apparently.
0935 Remove Cold Trap 1 from Dewar to let warm. Top off LN in Dewar to compensate for removing Trap 1.
1111 Isolate 1K Pot from pumping by closing V4a. Let P2 pump down remaining He from 1K Pot, then close valve on He4 pump. Open V11a, V7, V2a, and V5a to allow dirt from Cold Trap 1 to P2. P2 reads 120mbar of dirt.
1112 Open valve on He4 pump to pump out dirt from Cold Trap 1.
1114 When P2 reads 0.2mbar, close V11a, V7, V2a, and V5a. 1K Pot has reached 2.55K, P1 = 0.18mbar, G1/G2 increased by ~40mbar, and tower temperature has increased by ~0.6mK.
1115 Open V4a to begin pumping on 1K Pot again. 1K pot temp begins falling, oscillates, then stabilizes back to previous value.
1118 Put Cold Trap 1 back in LN2 bath.
1131 Switch He4 pump from Exhaust back to Recovery.
1140 Following the procedure from the Run Manual, switch to circulating through Cold Trap 1. P1 increased to 40mbar while extracting remaining mixture from Cold Trap 2 through V11a and V8, but quickly declined back to usual levels.
1221 P1 back at 0.11mbar. Close V11b and V8.
1225 Place Ba source at back of fridge inside top most part of shield.
1228 Start 30min run of Ba data at -/+10V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after. Use phonon trigger thresholds from last Wednesday
Rate drops to ~2Hz, so raise all phonon trigger thresholds by 20 ADC bins each:
A B C D
DIB1 56 60 62 60
DIB2 44 38 40 48
DIB3 60 66 78 68
1330 Main bath = 31.6%
1345 Start LHe transfer at 30.9%
1427 End LHe transfer at 90.9%
1431 Start 30min run of Ba data at +/-10V overshooting +Qbias (side 1) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after. Use phonon trigger thresholds listed above.
1633 Remove Ba source and place back in safe.
1635 Place Cf source inside shield near detector for overnight Cf data.
1640 Return phonon thresholds to Wednesday's values:
A B C D
DIB1 36 40 42 40
DIB2 24 18 20 28
DIB3 40 46 58 48
1641 Start 16 cycles of 30min runs of Cf data at -/+2V, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.

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