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2021/09/16 (Thursday)

Lab in-personnel: Giulia and Matt

Status	Run 74 in progress. First cooldown after IVC rebuild.
	Tower thermometer is reading high, probably this is a thermometer problem and the actual temperature is much lower. High noise in some of the charge channels.
	Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/~~Source_mover_board~~+HV_diverter_board → DCRC50(3)/55(1). Kepco 40V supplye → HV BNC. Lead shield erected, 4 walls. Currently both DCRCs are on.
	Position of Am source: y = 0.0 mm
	Circulation is suspended so we can explore data at higher temperatures. 1K Pot is still on.
0838	Tower/MC/Coldplate = 1682/11629/3057 mK, Still = 2.27 K / 1000.0 mbar / 0 mW, G1/G2= 32800/33600 mbar, 1K Pot = 1.56 K / 10±1 mbar. MB = 75.2%.
0844	Fill LN2 cold trap bath
0900	At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 3.2/1.5/2.0/29 8e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 550/3.7/4.1/14 e-6.
	Noise is lower than yesterday.
0930	Set MC heater → 2000 uW
1030	Tower temperature hasn't changed much Increase MC heater → 5000 uW
1100	Tower = 1.92 K, seems to be leveling
1100	Increase MC heater → 10000 uW
1200	Tower = 2.10 K, flat
1202	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/25/30/120 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_takeandflash_dcrcbias.msl. This flashes for 30 seconds at end of series.

07210916_1202

1520	Increase MC heater → 20000 uW
1530	Tower = 2.7 K and rising in a sort of runaway fashion… Turn off MC heater for now
1640	Have been messing around with different heater settings, seems a little difficult to keep it stable in this temperature regime (2.1-2.8 K) with the 1K Pot on at least.