2022/07/19 (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 → DCRCX(4) Lead/poly shield fully assembled. Boron-filled socks covering NaI detectors. PuBe on North side of lead/poly shield. |
| 1155 | MC/Coldplate = 29.3/156 mK, Still = 1.13 K / 0.110 mbar / 0 mW, G1/G2 = 120/130 mbar, 1K Pot = 60° / 1.54 K / 7.5±0.5 mbar, MB = 41.7% |
| 1200 | Fill LN2 cold trap bath |
| 1225 | Put PuBe drum back behind lead wall on West side of shield. |
| 1347 | Begin LHe transfer @ MB = 36.6% |
| 1632 | End LHe transfer @ MB = 90.4% |
| Transfer had some issues. At the end pressure went very high, around 6 PSI, meter got frosty and started clicking. Waited extra long with the stick raised and the Dewar connected to recovery (15 min instead of 10 min) to get the pressure low enough to end the transfer. Maybe I let the level get to high and we got violent boiloff at the end. (Although level was kind of low after I finally disconnected.) Reco efficiency looks low for this cycle, 89.4% c/w typical 95%. | |
| 1655 | Move PuBe drum to North side of lead/poly shield |
| 1655 | Start an overnight NaI array scan. Take separate PuBe scans for a set of detectors: even-numbered 6-22 plus redo 9.15,17. Should nominally run 19.6 hours ending tomorrow around 12:30 pm |