2022/04/13 (Wednesday)
- Lab in-personnel: Matt
| Status | Run 76 in progress |
|---|---|
| Setup | Cable 2/1/3 → diverter/nothing/nothing → HV CONN1/2/3 → HV 1/2 → DCRC50(3)/DCRC55(1), DCRC33(2)→HV control, NaI trigger signal → DCRC52(6) actually discovered later that Cables 1&3 were swapped. |
| 1630 | MC/Coldplate = 27.7/140 mK, Still = 1.05 K / 0.110 mbar / 0 mW, G1/G2= 137/143 mbar, 1K Pot = 18° / 1.59 K / 13±2 mbar, MB = 24.0% |
| 1630 | Goldman = 68.8 mK @ 632 uV excitation |
| 1630 | Fill LN2 cold trap bath |
| 1725 | Setting up remote-control HV. DCRC2 connected to Kepco HV control. With DCRC2qI = 0V, dial Kepco up to 250V. (It's not connected to the HV box of course.) |
| 1730 | Try finding DCRC2qI setting to set Kepco to 0V. Looks like DCRC2qI=11.57 → HV = ~ 10 mV (minimum) |
| 1730 | With HV still at minimum plug HV into HV box. No effect on phonon channels, good pulses all around. |
| 1745 | Use Root Sequencer to step DCRC1qI from 11.57 down to 6.94 over a total time of 20 seconds. Takes the bias up to +98.8 V. Shortly after bias starts rising, jagged noise shows up, then pulses disappear - looks like channels went normal. Baselines elevated. MC temperature rises too though there is a delayed effect. |
| 1750 | Use Root Sequencer to dial HV back to 0V. Temperature starts falling again: increase was very slight actually, 27.7→27.8 mK. Pulses come back, baselines fall back to normal. |