2019/04/01 (Monday)
| Setup | DIB1/3/4 → 3.2 MHz filters 2/3/1 → cable 3/1/2 → gender changer 3/?/2 → HVConn 1/3/2 → HV 1/2 → DCRCX(4)/DCRC50(3) DCRC33(2) → 1kV power supply → HV input Lead poly shield is erected, N/E/W walls complete, no poly or lead on S wall. |
|---|---|
| 0658 | Start a background series at HV = 300→400V @ 3.9 V/min (26 min duration) with 1 minute 15% prebias CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (430/410/500)/(500/460/420) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR randoms, trigger on DCRC4pA/B/C threshold = 7/6/6 use sequence looptest_HVdrift_fast_300V_3p9VPM_prebias_15_1_dur_26min.msl |
| 0835 | Tower/MC/Coldplate = 39.8/29.8/181 mK, Still = 1.60±0.15 K / 0.150 mbar, G1/G2 = 281/259 mbar, 1K Pot = 1.78 K / 13 mbar. MB = 37.3% |
| 0850 | Fill LN2 cold trap bath. |
| 0920 | Try closing inlet valve to 4He pump for a few seconds. Spike in 1K Pot pressure and temperature, then it recovers immediately. Still spikes from 0.15 to 0.17 mbar and back. Slight spike in Tower temperature, rises about 0.5 mK then falls back. |
| 1515 | Start LHe transfer @ MB = 27.7% |
| 1555 | End LHe transfer @ MB = 93.4 % |
| 1706 | Fill LN2 cold trap partially. Need to refill LN2 dewar. |
| 1730 | MB = 91.5 % |