2022/07/01 (Friday)
- Lab in-personnel: Matt, Giulia, Zach, Himangshu
| 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. |
| 1100 | MC/Coldplate = 29.2/153 mK, Still = 1.08 K / 0.095 mbar / 0 mW, G1/G2 = 141/141 mbar, 1K Pot = 60° / 1.55 K / 8.0±0.5 mbar, MB = 42.1% |
| 1106 | Filled LN2 cold trap dewar |
| 1418 | PuBe source is in PAN 43 now on platform behind lead wall |
| 1430 | Set the NaI trigger window to target high energy gammas from n-capture. Targeting a trigger window of 7600-11200 keV. On the Linux NaI DAQ machine go to ~/packages/R76-Firmware/library/C/lib and enter command ./setregisters -t10760 -T15760 -v3. |
| This trigger window should be pretty low rate. Try triggering MIDAS on the NaI (DCRC4pA) for a minute - yep, looks like less than 1 Hz. | |
| 1435 | Check phonon channels. Had to adjust offset on DCRC3pB. It was 0.4 a while ago, now -0.7. All baselines around -0.8 V. |
| 1439 | Start 0 V PuBe data series 66 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 1619 | Begin LHe transfer @ MB = 34.9% |
| 1705 | End LHe transfer @ MB = 93.7% |
| 1730 | Check phonon channels, look good. |
| 1735 | Dial HV up to -227.2 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
| 1735 | MC = 29.0 mK |
| 1740 | After 5 minutes dial HV down to -195.35 V |
| 1745 | Pulses in most channels look fine, some seem to have somewhat elevated baselines. DCRC3pB has ugly jagged noise though. |
| 1750 | Check Vtest in the HV box: -83 mV, that's very high. That means only 81% of the HV is reaching the detector. I should check the purge gas for the Ebox, see if it's flowing. |
| 1750 | LN2 Dewar vent valve looked like it was completely closed. Open it up to get a tiny amount of flow going to the purge bag. |
| We'll bring the HV back down and try again later. | |
| 1755 | Dial HV back down to 0V |
| 1805 | Pulses look better @ 0V but DCRC3pB still shows some remnants of screwy noise maybe. Let's zap the SQUIDs. |
| 1805 | Zap SQUIDs on DCRCs 1&3 |