2022/05/03 (Tuesday)
- Lab in-personnel: 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 → DCRC52(6) |
| 0820 | MC = 28.2 mK |
| 0820 | DCRC3 channel baselines are higher then before, not sure why |
| 0825 | DCRC3 pB&D restored to normal -0.8 to -0.9 V baseline with relocks, pA needed its offset adjusted. |
| 0829 | Dial HV up to -274.1 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
| Baselines are definitely elevated, pulse amplitudes low. We'll see how it looks after ending prebias. | |
| 0834 | MC temperature rises sharply to 37 mK, falls again. That's not good… Phonon channels now barely showing pulses, highly elevated, some railed. |
| 0836 | After 5 minutes dial HV down to -238.1 V |
| 0837 | MC = 32 mK and falling |
| 0839 | DCRC1 channels railed. Some DCRC3 channels showing good pulses, others showing highly distorted pulses… |
| 0840 | Zap SQUIDs in DCRCs 1&3 |
| 0850 | Readjust DCRC3pA offset to what it was before. Channels look OK. |
| 0851 | Start -238.3 V data series after 5 min 13% prebias, 57 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 0855 | MC = 29.2 mK, high. It fell to 28.7 mK after the zap but then rose again. |
| 0905 | MC = 28.6 mK |
| 0920 | MC = 28.3 mK |
| 0950 | Dial HV down to 0V after data series ends. |
| 1210 | MC/Coldplate = 28.3/146 mK, Still = 1.09 K / 0.100 mbar / 0 mW, G1/G2 = 100/96 mbar, 1K Pot = 18° / 1.56 K / 10±1 mbar, MB = 72.8% |
| 1210 | Goldman = 52.8 mK @ 63.2 uV excitation. Note this is much lower than it has normally been reading in this run, and also that I didn't have to increase the excitation - 63.2 uV is the default I've been using for this run, but for Goldman I had to increase it before or the bridge wouldn't read it. |
| 1215 | Fill LN2 cold trap bath |
| 1247 | Sudden change in Goldman thermometer readout. No longer reads at 63 uV, have to increase to 200 uV. At that excitation Goldman temperature rises to 71 mK, more in line with earlier readings. |
