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2021/09/26 (Sunday)

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.
	The interesting oscillating pattern in the 1K Pot is also seen in the Sorb thermometer. Pot temperature & pressure and Sorb temperature oscillating in phase with a 10 minute period. Sorb = 4.0-4.3 K, 1K Pot 3.15-3.43 K, 1.3-1.6 mbar.
0831	Start 2 series of 0V / +10/0V noise-only data (0831,0832) 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 = 3.86-3.87 K
0839	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 = 3.91-3.97 K during series, up and down as I adjusted the MC heater (near the end it rose to 4.02 K)


07210926_0839

0956	Start 2 series of 0V / +10/0V noise-only data (0956,0957) 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 = 4.90-4.93 K
1006	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 100/80/50/120 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.
	Adjusted triggers upward during series, biased noise is pretty high and choppy at this temperature
	Tower = 4.93-5.07 K during series, up and down as I adjusted the MC heater


07210926_1006

1115	Start 2 series of 0V / +10/0V noise-only data (1115,1116) 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 = 5.58-4.60 K
1125	Tower/MC(H35)/MC(Cernox) = 5542/6958/5784 mK, Still = 5.58 K, 1K Pot = 3.43 K / 10±1 mbar. MB =06.0%
1129	Fill LN2 cold trap bath.
1140	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 120/100/50/150 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.
	Adjusted triggers upward during series, biased noise is pretty high and choppy at this temperature
	Tower = 5.54-5.58 K during series, up and down as I adjusted the MC heater


07210926_1140

1459	Start 2 series of 0V / +10/0V noise-only data (1459,1500) 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 = 6.08-6.10 K
1536	Start 45 min series of +10/0V data (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 60/50/50/80 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.
	Adjusted triggers upward during series, biased noise is pretty high and choppy at this temperature
	Tower = 6.09-6.14 K during series, up and down as I adjusted the MC heater


07210926_1536

1714	Start 2 series of 0V / +10/0V noise-only data (1714,1715) 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.
	Actually edited this sequence so that the second series continued for 2min45sec, then tried setting trigger thresholds. I'd noticed in the last series that no pulses could be seen over the noise, and that's true in this case too - looks like zero charge collection efficiency. So I'm not bothering with the usual 45 minute series.
	Tower = 6.57-6.59 K
1750	Start 2 series of 0V / +10/0V noise-only data (1750,1751) 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 = 7.10-7.13 K
1815	Start 2 series of 0V / +10/0V noise-only data (1815,1816) 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 = 7.71-7.75 K
1842	Start 2 series of 0V / +10/0V noise-only data (1842,1843) 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 = 8.48-8.54 K
1911	Start 2 series of 0V / +10/0V noise-only data (1911,1912) 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 = 9.54-9.58 K
1944	Start 2 series of 0V / +10/0V noise-only data (1944,1945) 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 = 10.52-10.56 K
2005	Start pumping mixture out of fridge and cold LN2 Trap 2 to dump. 1K Pot temperature rises to around 6 K. Close V4a to stop pumping on 1K Pot.
2310	Dump = 744.1 mbar, Fridge(P1) = 0.017 mbar, Tower = 7.29 K, Sorb = 15.4 K
2315	Stop pumping mixture to dump. (NOTE: remember to close V13a Speedivalve, also 1K Pot speedivalve.) Close V9 and turn off 3He pump.