2017/06/12 (Monday)

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	Setup: DIB1/3/4 → 3.2 MHz filters 3/1/2 → cable 3/1/2 →gender changer 3/1/2 → HVConn 1/3/2 → HV 1/2 → DCRC55(1)/DCRC33(2)
	PuBe source in paraffin barrel behind shield (west side)
0035	most recent data looks OK, in terms of having channels not railed, the voltage has been drifting though
0035	Leakage is at Vtest = 69.41 mV → Vdetector = 46.8 V
0036	Tower/MC/Coldplate = 33/29.6?/193 mK, Still = 1.27 K / 0.110 mbar, G1/G2 = 228.2/218.8 mbar, 1K Pot = 1.66 K / 19.0 mbar. Main bath = 47.6%. Predicted level: %
0043	sequence finished, turn voltage down and let settle
0047	begin 900s bake Lab = 24.4 C humidity = 41%
0109	begin pre-bias, start with HV = 90 V
0120	settled at HV = 110 V, Vtest= 107.45 mV → Vdetector = 67 V
0129	got to 50V, start at HV = 73 V
0141	ended up at HV = 80.1 V, Vtest = 75.14 mV → Vdetector = 50.01 V
0143	tower temp not quite cool Tower = 34.1 mK, close enough
0144	Start 5 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, with 1000 beginning randoms, no flashing, and a 500ADC bin threshold trigger on DCRC4 pA (external trigger). Running OR trigger of NaI detectors with PuBe source on west side of shield. NaI detector C has 311 mV threshold and detector B has 288 mV threshold.
0905	Tower = 33.0 mK, Main bath = 34.5 % HV = 80.1 V, Vtest = 70.1 mV → Vdetector = 52.0 V Lab = 23.1 C, 41% humidity
0925	Dial HV down to zero and short leads
0930	Fill LN2 cold trap bath
0955	Begin 30 minute bake with DCRCs 1&2
1130	Dial HV up to 80.0 V. Will need to go higher for prebias… try 100 V
1140	Lab = 22.7 C, 42% humidity
1150	HV = 100 V, Vtest = 97.89 mV → Vdetector = 60.7 V. Begin dialing down to target Vdetector = 50V
1200	Try reestablishing N2 purge at the ebox by running a hose from the vent of the LN2 Dewar, and opening the valve slightly, just enough to feel some flow.
1202	Already the leakage current is falling quickly. Gleak was 1.3 nS when I started, now down to 0.21 nS Vtest fell from 20 mV to 16 mV over a couple minutes, still settling.
1210	HV = 82.4 V, Vtest = 9.78 mV → Vdetector = 78.4 V. Much lower leakage. Start decreasing HV to target Vdetector of 50 V.
1225	HV = 52.47 V, Vtest = 4.16 mV → Vdetector = 50.80 V. Adjust again.
1230	HV = 51.65 V, Vtest = 4.08 mV → Vdetector = 50.01 V
1234	Start 5 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, with 1000 beginning randoms, no flashing, and a 500ADC bin threshold trigger on DCRC4 pA (external trigger). Running OR trigger of NaI detectors with PuBe source on west side of shield. NaI detector C has 311 mV threshold and detector B has 288 mV threshold.
1250	HV = 51.65 V, Vtest = 3.95 mV → Vdetector = 50.06 V
1310	HV = 51.60 V, Vtest = 3.93 mV → Vdetector = 50.02 V
1330	HV = 51.57 V, Vtest = 3.77 mV → Vdetector = 50.06 V
1400	HV = 51.48 V, Vtest = 3.76 mV → Vdetector = 49.97 V
1425	Lab = 22.6 C, 42% humidity
1500	HV = 51.48 V, Vtest = 4.04 mV → Vdetector = 49.86 V
1530	HV = 51.62 V, Vtest = 4.05 mV → Vdetector = 49.99 V
1600	HV = 51.90 V, Vtest = 4.79 mV → Vdetector = 49.98 V
1605	Tower = 33.1 mK, Main bath = 22.8%. Bath calculator predicts 0% at ~~10:04 am tomorrow morning~~ NO - I used “now()” in the online spreadsheet but this was the wrong time zone! Actual prediction was 5:04 am.
1620	Fill LN2 cold trap bath. Temporarily stopping Ebox purge to do this. Will watch leakage for changes and continue to adjust HV.
1630	HV = 51.80 V, Vtest = 4.60 mV → Vdetector = 49.95 V
1640	Restore purge hose. Doesn't look like leakage changed much over that short time.
1655	Lab = 22.6 C, 42% humidity
1655	HV = 51.73 V, Vtest = 4.31 mV → Vdetector = 50.00 V
1737	HV = 51.73 V, Vtest = 4.25 mV → Vdetector = 50.03 V, pretty stable so far
1739	Lab = 22.9 C, 42% humidity
1739	turn down voltage, let settle
1744	ground detector and begin 1800s bake
1913	ramp detector up for pre-bias try HV = 65V !
1920	Lab = 23.4 C, 42% humidity
1930	settled near HV = 68.8 V, Vtest = 7.17 mV → Vdetector = 65.1 V, now can go to 50 V
1947	HV = 51.62 V, Vtest = 4.04 mV → Vdetector = 50.00 V
1948	Start 5 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, with 1000 beginning randoms, no flashing, and a 500ADC bin threshold trigger on DCRC4 pA (external trigger). Running OR trigger of NaI detectors with PuBe source on west side of shield. NaI detector C has 311 mV threshold and detector B has 288 mV threshold.
2340	HV = 51.62 V, Vtest = 4.71 → Vdetector = 49.73 V, pretty stable

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