2022/08/12 (Friday)
- Lab in-personnel: Giulia, Matt
| Status | Run 76 in progress |
|---|---|
| Setup | Cables 2/3/1 → diverter/nothing/nothing → Side2-readout HV CONN 1/3/2 → HV 1(L)/2(R) → DCRC50(3)/DCRC55(1), DCRC33(2)→HV control, NaI trigger signal → DCRCX(4) Lead/poly shield fully assembled. Boron-filled socks covering NaI detectors. PuBe behind lead wall on West side of lead/poly shield. |
| 1130 | MC/Coldplate = 28.3/149 mK, Still = 1.13 K / 0.130 mbar / 0 mW, G1/G2 = 165/152 mbar, 1K Pot = 50° / 1.64 K / 26±2 mbar, MB = 69.3% |
| 1142 | Fill LN2 cold trap bath |
| 1230 | IVC = 19 nbar. Only slightly higher than yesterday. |
| 1230 | MC behavior has changed again. Fell to 28.4 mK base, spikes to 29 mK spaced a few hours apart, with smaller spikes too but not very frequent. |
| 1245 | Look at phonon traces, seeing only very weak pulses |
| 1320 | Do IbIs curve for DRC1pA. Surprisingly it looks like we need higher QET biases than before, looks like it was superconducting at the previous QET bias of 181 - now can get dP/dI = 1.0 uV at QET bias 246.7 uA. |
| 1435 | MiniIbIs on DCRC1pB to find QET bias for dP/dI = 1.0 uV: was 189.5, now 244.0 uA. |
| 1500 | MiniIbIs on DCRC1pD to find QET bias for dP/dI = 1.0 uV: was 229.6, now 295.1 uA. |
| 1540 | Trying IbIs on DCRC3pA - acts like it's always in s/c, can't snap it out… |
| 1555 | Was able to get DCRC3pA out of s/c by cranking QET bias up to 900. Stepping it down from there it looked like it was in the normal state. Going below 500 it started to look like it was approaching a peak… but there was a lot of low-frequency noise, wavy-looking trace. At 440 uA it seemed to fall back into s/c. No pulses seen along the way. |
| 1640 | Using smaller steps I got DCRC3pA into transition. QET bias for dP/dI = 1.0 uV: was 188.1, now 242.4 uA. |
| 1710 | MiniIbIs on DCRC3pB to find QET bias for dP/dI = 1.0 uV: was 193.6, now 212.5 uA. |
| 1740 | MiniIbIs on DCRC3pB to find QET bias for dP/dI = 1.0 uV: was 210.7, now 242 uA. |
| 1800 | Adjust offsets to get all baselines near -0.8 V |
| 1805 | Start 0 V PuBe data series 83 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 15. Start series with the Start Button. |
| Temperature spike beginning 18:48 (28.6 mK), peaking at 18:50 (29.2 mK), then pretty close to base again by 18:55. We'll have to look and see if there's any sign in the data. | |
| 1940 | Tried to apply HV with the RootSequencer. But HP reading didn't change, although DCRC2 setting on ODB changed. Maybe something is not plugged in. Oh wait - DCRC2 wasn't enabled. Stop DAQ programs, enable DCRC2 only, restart programs. |
| 1945 | Dial HV up to -6.67 V with RootSequencer for 15% prebias |
| 1950 | Dial HV down to -5.76 V |
| 1955 | Check channels, look good. Not sure I understand the Vtest readout, maybe it's disconnected. |
| 1958 | Start -5.77 V PuBe data series 107 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 15. Start series with the Start Button. |
| 2152 | Dial HV down to 0V. Vtest responds, so I guess it is reading… but numerically it makes no sense, it was 125 mV during the series which seems impossible… |