| 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) |
| 1215 | MC/Coldplate = 28.5/145 mK, Still = 1.09 K / 0.100 mbar / 0 mW, G1/G2 = 118/111 mbar, 1K Pot = 18° / 1.57 K / 10±1 mbar, MB = 32.6% |
| | NOTE: we've been using Omni_Logger TestCopy_Himangshu.vi to get the Still and Coldplate temperatures. But since the beginning of the run this has given a Coldplate temperature of exactly 140 mK every time with no variation. Today I decided to look up the calibration curves and manually calculate the temperatures from the resistance readouts on the bridge. Still was the same as the vi but Coldplate was a little different, 146 mK. I found that the LakeShore bridge needs to have it's channel manually switched in order to get a fresh reading from the vi. I think the vi was just getting the last scanned value all this time… |
| 1245 | Fill LN2 cold trap bath |
| 1400 | Reset the HV maximum. First, unplug HV cable from HV box. Next, use RootSequencer to dial to current HV max (-250 V) by dialing DCRC2qI down from 11.64 to 0 V. Next, on Kepco supply dial HV up to -350 V - that's the new maximum. Note: that's too high to read on the HP supply (max 300 V), so instead I used the Fluke multimeter to set it to 350. Finally dial HV back down to 0V using the RootSequencer. |
| 1410 | The DCRC1qI value to get to HV = 0 has shifted a little, previously 11.64 now 11.66. (Not exactly zero, around HV = -45 mV.) |
| 1507 | Begin LHe transfer @ MB = 28.8% |
| 1553 | End LHe transfer @ MB = 95.6% |