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2016/08/27 (Saturday)

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Setup: DIB1/2/3 → 3.2 MHz filters → nothing/disconnector board/remapping board → HVside2board → DCRC55(1)/50(3). Disconnector board has all charge lines disconnected.
DCRCs powered overnight. Not pumping on IVC.. Baked detector in grounded HV mode for 12 hours overnight, Tower at 0.33 K until 04:48.
1043 Tower/MC/Coldplate = 37.9/29.4/157 mK, Still = 1.39 K / 80 μbar, G1/G2 = 179/162 mbar, 1K Pot = 1.54 K / 4.5 mbar, MB = 32.4%. IVC=7.4 μbar.
1049 DIB1PC baseline=-0.75V. Pulses look typical (i.e. not “peaky” as we expect to see from He film)
Increase HV until pulses disappear at 41.5V. 62.7mV leakage.
Pulses+breakdown noise return after ~1 min.
Decrease HV to 38V where pulses look good and baseline = -0.66V, 57.2mV leakage.
Breakdown limit = 12.8 V
1100 Increase HV until pulses disappear at -32.5V. -50.3mV leakage.
Pulses+breakdown return noise after ~1 min.
Decrease HV to -28.3 V where pulses look good and baseline = -0.69V, -41.9mV leakage.
Breakdown limit = -5.36V
1129 Commence LHe transfer. (31.4%)
1140 LN2 dewar empty, but so is the dewar in the fill room :/ Filling our LN2 dewar.
1301 Cease LHe transfer (90.6%)
1310 Release MB pressure.
1311 Fill LN2 cold trap full.
1318 Start 12 hour bake with HV grounded.

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