2021/08/18 (Wednesday)
- 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. No lead/poly shield. Currently both DCRCs are on. | |
| Position of Am source: y = -5.01 mm (mostly over blocker) | |
| now we'll move the source back to the center (doing this from home) | |
| 0851 | Do mvNwait +4steps×76 times, 40 second wait, with dwell = 40 and power = 6.8 V. (Around 5.93 mm/hour) This sequence will take 50min40sec and will move the source a total distance of 5.01 mm. Should end at 9:41 pm. Mean Tower temperature settles around 1.71 K during move. |
| 0940 | Tower/MC/Coldplate = 1821/176.4/242 mK, Still = 1.35 K / 0.095 mbar / 0 mW, G1/G2= 324.1/296.7 mbar, 1K Pot = 1.59 K / 20±1 mbar. MB = 35.2%. |
| The values above were recorded while the source was moving. | |
| 0952 | Fill LN2 cold bath. |
| 1115 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 1.7/1.1/1.3/5.0 8e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 8.5/1.9/2.0/16 e-6. |
| Noise is considerably lower than yesterday. | |
| 1210 | Tower/MC = 121/36.0 mK. |
| 1215 | Turn on MC heater to 300 μW. We'll try taking data at an elevated temperature again (last time was July 23 |
| 1245 | MC = 436 mK and flat. Tower = 404 mK and flat. |
| 1305 | Start 50 min series of 0V/-10V (bias applied after 60 sec), at elevated temperature, with 1000 beginning randoms, trigger threshold 60/50/70/100 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
 |
| 07210818_1305. No difference between this 0.4 K data and base temp data |
| 1400 | Dial bias to 0V. |
|---|---|
| 1400 | Turn off MC heater. |
| 1410 | Flash detector for 10 minutes with DCRC1&3 LEDs. |
| 1545 | Erect lead shield around fridge. 4 walls (no top pieces). |
| 1635 | Tower/MC = 92/35.7 mK |
| 1634 | Start 45 min series of 0V/-10V (bias applied after 60 sec), with shield present, with 1000 beginning randoms, trigger threshold 50/40/40/60 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| 1719 | Dial HV down to 0V and flash for 10 minutes with DCRC1&3 LEDs. |
 |
| 07210818_1634 |
| 1658 | Begin LHe transfer @ MB = 24.2 % |
|---|---|
| 1731 | End LHe transfer @ MB = 91.3 % |