2022/11/23 (Wednesday)
- 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 behind lead wall on W side of fridge. NaI array trigger window = 4.73 - 5.13 MeV |
| Warmed up yesterday for twenty-sixth 5K pumpout. Turbopumping IVC overnight. | |
| 1029 | MB = 1.5% |
| 1117 | Begin LHe transfer @ MB = 0.5% |
| 1120 | Turbo on IVC = 0.74 nbar. With Turbo valved out for 1 minute IVC = 8.6 nbar. |
| 1125 | Close IVC valves at top of fridge. |
| 1130 | MC = 5.72 K |
| 1130 | MB = 24.2% |
| 1130 | 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 = 0.32 bar on mechanical gauge. |
| 1135 | Fill LN2 cold trap bath |
| 1135 | 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. |
| 1140 | 4He pump valve open all the way. |
| 1140 | 1K Pot = 3.22 K / 2.0 mbar. G1 (fridge+dump)=419 mbar. MC = 5.67 K. |
| 1145 | 1K Pot = 3.17 K / 2.0 mbar. G1 (fridge+dump)=407 mbar. MC = 5.66 K. |
| 1215 | 1K Pot = 3.02 K / 1.9 mbar. G1 (fridge+dump)=377 mbar. MC = 3.27 K. |
| 1215 | Open 1K Pot needle valve → 15°. 1K Pot → 2.71 K / 5.5 mbar |
| 1218 | End LHe transfer @ MB = 96.4% |
| 1225 | Open 1K Pot needle valve → 30°. 1K Pot → 2.61 K / 7.0 mbar |
| 1235 | Open 1K Pot needle valve → 45°. 1K Pot → 2.36 K / 8.0 mbar |
| 1235 | MC/Still/1KPot = 2.99/2.83/2.30. G1(fridge+dump) = 275 mbar |
| 1245 | MC/Still/1KPot = 2.87/2.63/2.15. G1(fridge+dump) = 225 mbar |
| 1305 | MC/Still/1KPot = 2.56/2.26/1.73. G1(fridge+dump) = 132 mbar |
| 1440 | MC/Still/1KPot = 1.67/1.71/1.56. G1(fridge+dump) = 31 mbar, flattening. |
| 1440 | Close V3 and V9, leaving 30 mbar mixture in dump (G2) |
| 1440 | Turn on 3He pump. G1(condenser) → 40 mbar |
| 1440 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 245 mbar. MC(H35) → 1.30 K. Still → 1.33 K / 18 mbar |
| 1510 | V6 → 13.0%. Condenser(G1) peaks at 271 mbar. MC(H35) → 1.19 K. Still(P1) → 1.21 K / 5.5 mbar. |
| 1520 | V6 → 13.4%. Condenser(G1) peaks at 272 mbar. MC(H35) → 0.67 K. Still(P1) → 1.03 K / 1.0 mbar. |
| 1550 | V6 → 13.8%. Condenser(G1) peaks at 146 mbar. MC(H35) → 0.59 K. Still(P1) → 1.00 K / 0.6 mbar. |
| 1600 | V6 → 14.4%. Condenser(G1) peaks at 147 mbar. MC(H35) → 0.47 K. Still(P1) → 0.99 K / 0.4 mbar. |
| 1605 | V6 → 15.0%. Condenser(G1) peaks at 146 mbar. MC(H35) → 0.31 K. Still(P1) → 1.01 K / 0.28 mbar. |
| 1615 | V6 → 100.%. Condenser(G1) peaks at 143 mbar. MC(H35) → 0.18 mK. Still(P1) → 0.97 K / 0.075 mbar. |
| 1625 | Open V14 to pull the rest of the mixture out of the dump into circulation. Still peaks at 22 mbar, Condenser peaks at 188 mbar, MC peaks at 0.17 K, then all relax again. 1KPot = 1.55 K / 8.5±0.5 mbar. |
| 1650 | Still = 0.65 mbar. Close V14 |
| 1650 | MC = 52 mK |
| 1700 | Plug in DCRCs 1&3. Start DAQ programs. Get phonon baselines in approximately the right place. DCRC3pD has funny looking pulses, kinda plateaued. Try zapping SQUIDs, that doesn't seem to work yet with the DCRC2 DAQ. |
| 1710 | MC = 37 mK. Luckily the DCRC3pD pulses no longer look funny. But we will have to troubleshoot the zap tool at some point. |