2021/09/10 (Friday)
- Lab in-personnel: Giulia and Matt
| Status | Run 74 in progress. First cooldown after IVC rebuild. |
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| 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/ |
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| Position of Am source: y = 0.0 mm | |
| 0831 | Tower/MC/Coldplate = 87.8/33.9/193.4 mK, Still = 1.40 K / 0.070 mbar / 0 mW, G1/G2= 288.1/263.8 mbar, 1K Pot = 1.56 K / 10±1 mbar. MB = 72.5%. |
| 0839 | Fill LN2 cold trap bath |
| MIDAS seems frozen this morning (at least on the DAQ computer… seems to be working remotely) | |
| 0909 | Start 45 min series of -10V/0V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 80/40/30/150 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. |
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| 07210910_0909 |
| 1008 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 11/1.8/2.0/45 8e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 54/12/10/570 e-6. |
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| Noise is lower than yesterday. | |
| 1025 | Start 45 min series of -12V/0V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 70/40/35/160 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. |
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| 07210910_1025. Surprisingly low charge collection efficiency. |
| 1201 | Start 45 min series of +8V/0V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 60/30/30/150 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. |
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| 07210910_1201. Much lower impact ionization than the las +8/0V, seems to have fallen into a “low state” |
| 1331 | Start 45 min series of +10V/0V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 50/45/30/160 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. |
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| 07210910_1331. Detector's in a “low state” apparently. |
| Let's try data at elevated temperature again, see if it restores the detector to “high” impact ionization mode | |
| 1455 | Turn on MC heater to 800 uW |
| 1555 | Tower/MC = 1.022/1.133 K, seems to have settled |
| 1557 | Start 45 min series of +10V/0V (bias applied after 60 sec), Tower = 1.02 K, with 1000 beginning randoms, trigger threshold 100/50/40/200 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. |
| Adjusted trigger thresholds up a few times at the beginning because it seemed like there were trigger bursts. |
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| 07210910_1557 |
| 1650 | Turn off MC heater |
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