2019/03/18 (Monday)

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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 note: QET biases left at 0 overnight
0910	Tower/MC/Coldplate = 44.1/30.0/191 mK, Still = 1.70±0.20 K / 0.150 mbar, G1/G2 = 228/202 mbar, 1K Pot = 1.78 K / 16 mbar. MB = 42.8%
	Tower falling 1.1 mK/day
0920	Fill LN2 cold trap bath
1058	Start superconducting background series at HV = 0V CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = 0 uA, Front-End Gains = (4/2/3)/(10/15/10), trace length=65536 samples 1000 BOR randoms, then 20 Hz randoms
1103	Stop superconducting data
1114	Start normal-state background series at HV = 0V CDMS detector: Driver Gains = 1x, DCRC4/3 QET biases = 800 uA, Front-End Gains = (4/2/3)/(10/15/10), trace length=65536 samples 1000 BOR randoms, then 20 Hz randoms
1121	Stop normal-state data
1135	Get all 6 channels back into reasonable transition positions.
1145	Estimate event rate from looking at 30 52.488 ms traces in DCRC3pB, count a total of 155 pulses, so rate is 99±8 Hz.
1205	Install W and E walls of lead/poly shield
1230	Add 5 layers of 1/8“ thick lead sheets under cryostat. These fit between the posts with corner cut-outs for the posts. 22” N-S by 26“ E-W with 2”x2“ cutouts at corners (or a little bigger to accommodate the posts).
1255	Add 5 4 layers of 1/8” thick lead sheets on N and S sides of base of shield. These are 10“ by 26”.
	Note there are also permanent layers on the platforms, E and W sides, 10“ by 41”
1355	Estimate event rate from looking at 30 52.488 ms traces in DCRC3pC, count a total of 117 pulses, so rate is 74±7 Hz.
1440	Finish poly on North shield wall
1555	Begin LHe transfer @ MB = 33.2%
1600	Isolate 4He pump exhaust from recovery, so we can look for any change in between-transfer recovery efficiency.
1630	End LHe transfer @ MB = 92.1%
1650	Fill LN2 Cold Trap bath

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