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2019/04/04 (Thursday)

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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 → 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.
0900 Tower/MC/Coldplate = 39.7/29.8/189 mK, Still = 1.71±0.15 K / 0.150 mbar, G1/G2 = 298/264 mbar, 1K Pot = 1.77 K / 14 mbar. MB = 70.1%
0905 Fill LN2 cold trap full.
1050 Start a background series at HV = -300→-416V @ 2.9 V/min (40 min duration) with 1 minute 15% prebias
CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (440/380/430)/(500/460/410) uA, Front-End Gains = (2/2/3)/(5/2/5)
1000 BOR randoms, trigger on DCRC4pA/B/C threshold = 6/6/6DCRC4pA threshold = 6
use sequence HVdrift_300V_2p9VPM_prebias_15_1_dur_40min.msl
This rate might be a touch too high. I think we need to go down to 2.42 V/min
1228 Start a 60 min background series at HV = -300V with 1 minute 15% prebias
CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (440/380/430)/(500/460/410) uA, Front-End Gains = (2/2/3)/(5/2/5)
1000 BOR randoms, trigger on DCRC4pA/B/C threshold = 6/6/6DCRC4pA threshold = 6
use sequence HVconst_300V_prebias_15_1_dur_60min_flash.msl
1229 Vleak peaks at -30 mV
1237 HV/Vleak = -299.3V/-6.5 mV
1435 One point of these constant HV tests is to analyse noise level vs HV. However, when triggering, we don't get a great sense of the noise. Let's redo these tests with 5Hz in-run randoms as well. Set / Equipment / Triggerfe2 / Settings / RandomRate (Hz) 5
1438 Start a 60 min background series at HV = -300V with 1 minute 15% prebias
CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (440/380/430)/(500/460/410) uA, Front-End Gains = (2/2/3)/(5/2/5)
1000 BOR randoms, 5Hz in-run randoms, trigger on DCRC4pA/B/C threshold = 6/6/6
use sequence HVconst_300V_prebias_15_1_dur_60min_flash.msl
1555 Fill LN2 cold trap full.
1616 Change HV to positive polarity
1640 Start a 90 min background series at HV = 300V with 1 minute 15% prebias
CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (440/380/430)/(500/460/410) uA, Front-End Gains = (2/2/3)/(5/2/5)
1000 BOR randoms, 5Hz in-run randoms, trigger on DCRC4pA/B/C threshold = 6/6/6DCRC4pA threshold = 6
use sequence HVconst_300V_prebias_15_1_dur_90min_flash.msl
2000 Disable in-run randoms.
2004 Start 4x background series at HV = 300→400V @ 2.42 V/min (40 min duration) with 1 minute 15% prebias
CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = (440/380/430)/(500/460/410) uA, Front-End Gains = (2/2/3)/(5/2/5)
1000 BOR randoms, trigger on DCRC4pA/B/C threshold = 6/6/6DCRC4pA threshold = 6
use sequence HVdrift_4x300V_2p42VPM_prebias_15_1_dur_40min.msl
Looks like the drift rate is about right. Not sure what happened in that 2nd series to make the 60keV low.
Leaving out that 2nd series, we can see the activation and Am lines in Fpartition vs energy

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