2018/09/01 (Saturday)

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	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 → DCRC55(1)/DCRC50(3) 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V) / Ortec 575A(gain=10, shaping = 3us) → x10/x10 attenuator → DCRCX(4) DCRC33(2) → kepco 1kV power supply → HV input
status:	Took PuBe data overnight at -80V and -70V.
1045	Tower/MC/Coldplate = 30.4/29.3/183 mK, Still = 1.4±0.1 K / 0.070 mbar, G1/G2 = 134/128 mbar, 1K Pot = 1.60 K / 20 mbar, Turbo on IVC = 1.0 nbar, MB = 72.6%
1050	Fill LN2 cold trap bath.
1058	Start 10 x 2hr PuBe datasets at -80V split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-80×10-15_5PreBias-30Flash-30wait-2hrData-10minSubRun.msl CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = 10 NaI detector: 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V, Pos) / Ortec 575A(gain=10, shaping = 3us, Pos) → x10/x10 attenuator → DCRC4PB/PA, Driver Gains = 1/1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 64 (64 samples) 1000 BOR randoms, trigger on DCRC3pB/D threshold = 7/9
	Sequence should end around 14:00 tomorrow.
	Example of creating a data sequence script: [fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 80,80,80,80,80,80,80,80,80,80 -HVcalFile HV_DCRC2_control_cals_180807.txt -HVpreBias 15/5 -tSeries 120 -NsubSeries 12 -DCRCs2Flash 1,3 > ../../sequencer/HVscan-80×10-15_5PreBias-30Flash-30wait-2hrData-10minSubRun.msl
1200	Took LN2 dewar to be filled.
1252	Returned filled LN2 dewar, reconnected tube to ebox and continued purge.
1358	DCRC3pC is railed low. Change Driver Offset from 0 to -0.3
1406	DCRC3pC is still railed low. Change Driver Offset from -0.3 to -0.6
1424	DCRC3pC is still railed low. Change Driver Offset from -0.6 to -0.9
1430	DCRC3pC is still railed low. Change Driver Offset from -0.9 to -1.2
1430	Also HV leakage is very high. It started increasing at 12:00 when LN2 Dewar was removed. It's still high now.
1439	DCRC3pC is still railed low. Change Driver Offset from -1.2 to -1.5 ok I think this fixed it
1440	Vbias = -80.012 V, Vtest = -78.724 mV, so Vdetector only -48.5 V. Need to increase the purge flow.
1505	Vtest = -86.27 mV and getting worse. Open vent valve on LN2 Dewar further to increase ebox purge flow. Definitely flowing stronger now. Vtest immediately starts to improve.
1510	Vtest = -52 mV and falling.
1515	Vtest = -20 mV, starting to settle
1525	Vbias = -80.012V, Vtest = -15.525 mV, so Vdetector = -73.8 V.
2340	Vbias = -80.012V, Vtest = -11.986 mV, so Vdetector = -75.2 V. This looks like the typical value now.

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