2022/11/29 (Tuesday)
- Lab in-personnel: Zach
| 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 behind lead wall on W side of fridge. NaI array trigger window = 4.73 - 5.13 MeV |
| Warmed up yesterday for twenty-eighth 5K pumpout. | |
| 1020 | MC temp seems to have settled relatively high after the warmup, its now 9.68K |
| 1022 | Turbo on IVC = 0.74 nbar. With Turbo valved out for 1 minute IVC = 10 nbar |
| 1024 | Close IVC valves at top of fridge. |
| 1047 | Begin LHe transfer @ MB = 3.2% |
| 1051 | Fill LN2 cold trap dewar |
| 1103 | MB = 28.5% |
| 1104 | Turn on 4He pump. Open Recovery valve to 4He pump. Pump out line to 1K pot (speedivalve closed). Check pressure in 1K Pot (with V4a open, 4He pump inlet valve closed). 1K Pot = 0.42 bar on mechanical gauge. |
| 1110 | Pump out 1K Pot slowly, throttling the flow at the valve at the pump inlet, opening just until the pump gets louder, then waiting, then opening a little more, etc. With pump just a little loud, can see pressure go down at the mechanical gauge. When this is low, open valve a bit more. When P2 gets below 30 mbar open valve all the way. |
| 1113 | 4He pump valve open all the way. |
| 1114 | 1K Pot = 3.26 K / 2.8 mbar. G1 (fridge+dump) = 435 mbar. MC = 8.58 K. |
| 1117 | Open 1K Pot needle valve → 15°. 1K Pot → 2.88 K / 7.5 mbar |
| 1120 | 1K Pot settled to 3.04 K / 5.5 mbar |
| 1124 | Open 1K Pot needle valve → 30°. 1K Pot → 2.93 K / 7.0 mbar |
| 1125 | Unplug DCRCs, Matt forgot to yesterday |
| 1129 | 1K Pot settled to 2.80 K / 8.5 mbar |
| 1130 | Open 1K Pot needle valve → 45°. 1K Pot → 2.88 K / 8.5 mbar |
| 1135 | 1K Pot settled to 2.76 K / 9.5 mbar |
| 1139 | Ended LHe transfer @ MB = 94.8% |
| 1159 | MC/Still/1KPot = 2.98/2.83/2.30, G1(fridge+dump) = 280 mbar, falling linearly. |
| 1334 | MC/Still/1KPot = 1.74/1.77/1.52. G1(fridge+dump) = 36 mbar, flattening. |
| 1335 | Close V3 and V9, leaving 48 mbar mixture in dump (G2) |
| 1336 | Turn on 3He pump. G1(condenser) → 45 mbar |
| 1340 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 176 mbar. MC(H35) → 1.48 K. Still → 1.51 K / 80 mbar |
| 1350 | V6 → 13.0%. Condenser(G1) peaks at 196 mbar. MC(H35) → 1.37 K. Still(P1) → 1.40 K / 24 mbar. |
| 1400 | V6 → 13.4%. Condenser(G1) peaks at 230 mbar. MC(H35) → 1.21 K. Still(P1) → 1.25 K / 5 mbar. |
| 1410 | V6 → 13.8%. Condenser(G1) peaks at 174 mbar (and rises more shortly after). MC(H35) → 0.85 K. Still(P1) → 1.13 K / 2.8 mbar. |
| 1420 | V6 → 14.4%. Condenser(G1) peaks at 193 mbar. MC(H35) → 0.60 K. Still(P1) → 1.12 K / 1.5 mbar. |
| 1428 | V6 → 15.0%. Condenser(G1) peaks at 192 mbar. MC(H35) → 0.37 K. Still(P1) → 1.12 K / 0.80 mbar. |
| 1435 | V6 → 100.%. Condenser(G1) peaks at 187 mbar. MC(H35) → 0.16 mK. Still(P1) → 1.07 K / 0.19 mbar. |
| 1443 | Plug in DCRCs 1 and 3 |
| 1457 | Open V14 to pull the rest of the mixture out of the dump into circulation. Still peaks at 34 mbar, Condenser peaks at 189 mbar, MC peaks at 0.070 K, then all relax again. 1KPot = 1.57 K / 10±0.5 mbar. |
| 1535 | Still = 0.45 mbar. Close V14 |
| 1745 | Check phonon channels. Relock some, adjust offset on DCRC1pD. All baselines are around -0.8 V. Should wait for detector temperature to stabilize before tuning these. MC temperature is rising. |
| 2000 | Tune phonon offsets to get all baselines near -0.800 V |
| 2000 | MC = 28.6 mK. Rose from 27.7 mK before turning on the DAQ programs. |