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2021/09/25 (Saturday)

Lab in-personnel: Giulia

Status	Run 74 in progress. First cooldown after IVC rebuild. Circulation is stopped, taking data at >1K temperatures.
	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
	1K Pot not working well, we have it on with needle valve closed - it has some cooling power. Mixture is open to fridge, cold LN2 Trap 2, and dump, 3He pump off.
	Overnight, pot cooled things off. Like yesterday we can cool further by pumping condensed mixture out of the fridge.
0855	Tower = 3.30 K. G1(fridge) = 484 mbar. 1K Pot = 3.26 K / 2.0 mbar.
	In addition to standard +10/0 V datasets, should take biased noise data. It looks like at these higher temperatures, breakdown-ish noise appears after the bias is applied.
0908	Start 2 series of 0V / +10/0V noise-only data (0908,0909) with 1000 beginning randoms, each data series 1 minute only, one before the bias applied and the next just after. No triggers. With 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_noiseBeforeAndAfterBias.msl. This flashes for 30 seconds at end of series.
	Tower = 3.30 K
0922	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/40/30/60 on DCRC3qI/qO/DCRC1qI/qO, ~~5Hz~~no 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.
	Tower = 3.30 K during series


07210925_0922

1010	Start pumping mixture out of still side only (V3 closed) to dump, V6 = 12.8%
1015	Tower temperature falling fast, tried closing V6 and turning on the MC heater to try to get a constant temperature, but it kept going up even with the heater off. So, turn off heater and start pumping again, we'll let it get to some minimum then start the heater while it's pumping.
1030	Tower = 1.33 K, falling more slowly.
1043	Start 2 series of 0V / +10/0V noise-only data (1033,1044) with 1000 beginning randoms, each data series 1 minute only, one before the bias applied and the next just after. No triggers. With 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_noiseBeforeAndAfterBias.msl. This flashes for 30 seconds at end of series.
	Tower = 1.28-1.27 K
1056	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/40/30/60 on DCRC3qI/qO/DCRC1qI/qO, ~~5Hz~~no 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.
	Tower = 1.26-1.30 K during series, up and down as I adjusted the MC heater


07210925_1056

1116	Fill LN2 cold trap bath.
1347	Start 2 series of 0V / +10/0V noise-only data (1347,1348) with 1000 beginning randoms, each data series 1 minute only, one before the bias applied and the next just after. No triggers. With 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_noiseBeforeAndAfterBias.msl. This flashes for 30 seconds at end of series.
	Tower = 1.56-1.54 K
1357	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/40/30/60 on DCRC3qI/qO/DCRC1qI/qO, ~~5Hz~~no 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.
	Tower = 1.55-1.58 K during series, up and down as I adjusted the MC heater


07210925_1357

1520	Start 2 series of 0V / +10/0V noise-only data (1520,1521) with 1000 beginning randoms, each data series 1 minute only, one before the bias applied and the next just after. No triggers. With 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_noiseBeforeAndAfterBias.msl. This flashes for 30 seconds at end of series.
	Tower = 2.08 K
1530	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/40/30/60 on DCRC3qI/qO/DCRC1qI/qO, ~~5Hz~~no 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.
	Tower = 2.11-2.13 K during series, up and down as I adjusted the MC heater


07210925_1530

1648	Start 2 series of 0V / +10/0V noise-only data (1648,1649) with 1000 beginning randoms, each data series 1 minute only, one before the bias applied and the next just after. No triggers. With 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use Sequencer script r74_noiseBeforeAndAfterBias.msl. This flashes for 30 seconds at end of series.
	Tower = 2.63-2.68 K
1657	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 50/40/30/60 on DCRC3qI/qO/DCRC1qI/qO, ~~5Hz~~no 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.
	Tower = 2.66-2.71 K during series, up and down as I adjusted the MC heater


07210925_1657

1745	Turn off MC heater, close V6 to stop pumping on still, open V13b to let mix from dump into fridge, turn off 3He pump. We'll let it settle again, com back to it later.