2019/06/12 (Wednesday)

Previous Day

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)/DCRC55(1) DCRC33(2) → 1kV power supply → HV input Three walls of the lead/poly shield are up.
0920	Tower/MC/Coldplate = 42.3/30.8/199 mK, Still = 1.275 K / 0.090 mbar, G1/G2 = 153/144 mbar, 1K Pot = 1.63 K / 22 mbar. MB = 38.0% after several days in their “low” modes, Coldplate and Still thermometers are back in their “high” modes.
0925	Fill LN2 Cold trap bath
	Last night's data was taken with a HV drift rate of +2.34 V/min, but it looks like that's still a little low, by about 0.08 V/min. Let's adjust to 2.418 V/min = 0.0403 V/s. Let's make sequences for 180V, 200V, 220V.

[fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 200 -HVcalFile HV_calibrations/HV_DCRC2_control_cals_440V_190603.txt -HVdriftRate 0.0403 -HVpreBias 10/2 -tSeries 82 -DCRCs2Flash 1,4 > ../../sequencer/HVdrift_200V_2p418VPM_prebias_10_2_dur_82min_flashDCRC_1_4.msl
[fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 180 -HVcalFile HV_calibrations/HV_DCRC2_control_cals_440V_190603.txt -HVdriftRate 0.0403 -HVpreBias 10/2 -tSeries 90 -DCRCs2Flash 1,4 > ../../sequencer/HVdrift_180V_2p418VPM_prebias_10_2_dur_90min_flashDCRC_1_4.msl
[fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 220 -HVcalFile HV_calibrations/HV_DCRC2_control_cals_440V_190603.txt -HVdriftRate 0.0403 -HVpreBias 10/2 -tSeries 74 -DCRCs2Flash 1,4 > ../../sequencer/HVdrift_180V_2p418VPM_prebias_10_2_dur_74min_flashDCRC_1_4.msl

1030	Let's try a negative bias. Reverse the leads on the HV supply.
1035	Notice that the HV is not very close to zero. Adjust DCRC2qI from 11.537 to 11.58 and find it's much closer to 0V (-1.5V → -0.011V).
1050	Create a new HV calibration file HV_calibrations/HV_DCRC2_control_cals_440V_190612.txt
1055	Create a new sequence for 200V+2.481V/min with the new calibration file:

[fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 200 -HVcalFile HV_calibrations/HV_DCRC2_control_cals_440V_190612.txt -HVdriftRate 0.0403 -HVpreBias 10/2 -tSeries 82 -DCRCs2Flash 1,4 > ../../sequencer/HVdrift_200V_cal0612_2p418VPM_prebias_10_2_dur_82min_flashDCRC_1_4.msl

1105	Start an 82 min series at HV = -200→-400V, rate -2.418V/min with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 6/6/6. Use sequence HVdrift_200V_cal0612_2p418VPM_prebias_10_2_dur_82min_flashDCRC_1_4.msl
1232	Looks like the trigger rate is much too high, so increase DCRC1pB/C/D trigger thresholds to 8/8/8. Unfortunately this is pretty close to the end of the data series.
	At the end of the sequence adjust DCRC2qI to get HV closer to zero, it was around 1V
	The HV drift doesn't look fast enough for this -200V data, for some reason. Should be 0.0063 V/s faster, so let's try 2.796 V/min = 0.0466 V/s. Surprising that it needs to be so high.

[fritts@jiajin /home/hep/cdmssoft/scdmsDAQ/MidasDAQ/online/scripts/pysequencer]: python HVscan.py -iDCRC 2 -HVs 200 -HVcalFile HV_calibrations/HV_DCRC2_control_cals_440V_190612.txt -HVdriftRate 0.0466 -HVpreBias 10/2 -tSeries 71 -DCRCs2Flash 1,4 > ../../sequencer/HVdrift_200V_cal0612_2p796VPM_prebias_10_2_dur_71min_flashDCRC_1_4.msl

1344	Start a 71 min series at HV = -200→-400V, rate -2.796V/min with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 8/8/8. Use sequence HVdrift_200V_cal0612_2p796VPM_prebias_10_2_dur_71min_flashDCRC_1_4.msl

1344

Start a 71 min series at HV = -200→-400V, rate -2.796V/min with 10% prebias for 2 minutes, flash at end with 30 min wait.
CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5)
1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 8/8/8.
Use sequence HVdrift_200V_cal0612_2p796VPM_prebias_10_2_dur_71min_flashDCRC_1_4.msl

Noise width for this -200V series is around 38 eVee, significantly worse than for the +200V case

1420	Begin LHe transfer. MB = 30.8%
1500	End LHe transfer. MB = 89.3%
1550	Fill LN2 Cold trap bath
1630	Switch HV leads back to positive polarity. Also, the HV calibration seems to have shifted a little - adjust the HV_DCRC2_control_cals_440V_190612.txt a little, just the near-zero values - the higher biases don't seem to have changed significantly.
	We'll go back to the 2.418 V/min drift, which seemed correct for positive-bias data, even though for some reason we needed a faster drift for negative-bias. And we'll try the lower thresholds again.
1647	Start a 90 min series at HV = 180→400V, rate 2.418V/min with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 6/6/6. Use sequence HVdrift_180V_cal0612_2p418VPM_prebias_10_2_dur_90min_flashDCRC_1_4.msl
2022	Start a 74 min series at HV = 220→400V, rate 2.418V/min with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 6/6/6. Use sequence HVdrift_220V_cal0612_2p418VPM_prebias_10_2_dur_74min_flashDCRC_1_4.msl
2245	Start a 90 min series at HV = 180→400V, rate 2.418V/min with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/490)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR and 1000 EOR randoms, trigger on DCRC1pB/C/D threshold = 6/6/6. Use sequence HVdrift_180V_cal0612_2p418VPM_prebias_10_2_dur_90min_flashDCRC_1_4.msl

Next Day