2022/04/25 (Monday)
- 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) |
| 0715 | Dial HV up to -91.1 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
| 0720 | After 5 minutes dial HV down to -79.0 V |
| 0722 | Start -79.0 V data series after 5 min 15% prebias, 50 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 0725 | MC = 28.5 mK |
| 0815 | Dial HV down to 0V after data series ends. |
| 1115 | MC/Coldplate = 28.5/140 mK, Still = 1.09 K / 0.110 mbar / 0 mW, G1/G2= 114/109 mbar, 1K Pot = 18° / 1.57 K / 10±1 mbar, MB = 74.7% |
| 1115 | Goldman = 72.4 mK @ 632 uV excitation |
| 1135 | Dial HV up to -138.1 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
| Seeing a little sporadic excess noise, like weak breakdown | |
| 1141 | After 5 minutes dial HV down to -119.6 V |
| Looks like less noise | |
| 1144 | Start -119.6 V data series after 5 min 15% prebias, 58 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 1245 | Dial HV down to 0V after data series ends. |
| 1245 | Fill LN2 cold trap bath |
Analysis notes: from the three recent HV series I've calculated the noise width using the same procedure as I did in Run 75 (quadratic linearization of PTOF wrt PTINT, then 1-point calibration to 14keV). Here are the results:
| HV bias [V] | Noise width [eVee] (uncertainty ~ 0.3) |
|---|---|
| -98.4 | 4.99 |
| -79.0 | 5.41 |
| -119.6 | 4.39 |
It certainly looks like we keep getting better with increasing bias. But that's if we trust the calibration method. Of course the 14keV line gets more and more saturated, so we should think about it more.
| 1615 | Dial HV up to -161.9 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
|---|---|
| 1620 | After 5 minutes dial HV down to -140.5 V |
| 1621 | Start -140.5 V data series after 5 min 15% prebias, 58 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 1720 | Dial HV down to 0V after data series ends. |
| 2010 | Check the channels - several are railed. Let's maybe try zapping. |
| 2015 | Zap SQUIDs on DCRCs 1&3 |
| 2020 | Adjust offsets to get phonon baselines in the -0.8 to -0/9 V range |
| 2025 | Dial HV up to -184.6 V using RootSequencer for prebias. Set it to rise about 5 V/s with 0.25 second steps. |
| MC = 29.6 mK. It has drifted up after cooling down after the zap | |
| 2030 | After 5 minutes dial HV down to -160.3 V |
| 2032 | Start -160.8 V data series after 5 min 15% prebias, 61 min long, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC3pD threshold 10. Start series with the Start Button. |
| 2135 | Dial HV down to 0V after data series ends. |