2022/10/06 (Thursday)
- 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 source behind lead wall on West side of lead/poly shield. |
| NaI trigger window: 7.6-11.2 MeV | |
| Warmed fridge two days ago for twelth 5K pumpout. Turbopumping IVC for the last two days. | |
| 1025 | MC/1KPot/Sorb = 5.36/6.98/8.9 K. G1(fridge) = 552 mbar |
| 1025 | Turbo on IVC = 1.2 nbar. With Turbo valved out for 1 minute IVC = 12 nbar. |
| 1030 | Close IVC valves on top of fridge |
| 1030 | 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 = 0.23 bar on mechanical gauge. |
| 1030 | Pump out 1K Pot in stages, alternating 1K Pot Speedivalve and V4a, opening V4a in brief spurts to keep 4He pump pressure low (below 5 mbar). |
| 1035 | Start pumping 1K Pot continuously |
| 1100 | MC = 3.44 K. Dropped quickly to this point, then started cooling more slowly. |
| 1345 | MC/1KPot = 2.55/2.12 K. G1(fridge) = 143 mbar |
| 1345 | 1K Pot = 0° / 2.11 K / 2.4 mbar |
| 1345 | Open 1K Pot needle valve → 15°. 1K Pot → 1.78 K / 5.5 mbar |
| 1355 | Open 1K Pot needle valve → 30°. 1K Pot → 1.56 K / 8.0 mbar |
| 1400 | Open 1K Pot needle valve → 45°. 1K Pot → 1.57 K / 10 mbar |
| 1405 | MC = 2.14 K. G1(fridge) = 70 mbar |
| 1445 | MC = 1.87 K, it kinked at 2.1 K (lambda point). G1(fridge) = 47 mbar |
| 1450 | Fill LN2 cold trap bath |
| 1500 | MC = 1.78 K. G1(fridge) = 40 mbar |
| 1500 | Close V3 and V9, leaving 30 mbar mixture in dump (G2) |
| 1500 | 1K Pot = 1.59 K / 11±1 mbar |
| 1505 | Turn on 3He pump. G1(condenser) → 46 mbar. |
| 1505 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 236 mbar. MC(H35) → 1.55 K. Still → 1.51 K / 50 mbar |
| 1510 | V6 → 13.0%. Condenser(G1) peaks at 272 mbar. MC(H35) → 1.25 K. Still(P1) → 5.5 mbar. |
| 1515 | V6 → 13.4%. Condenser(G1) peaks at 223 mbar. MC(H35) → 1.06 K. Still(P1) → 3.2 mbar. |
| MC kinked around 1.18 and 1.06 K, Al transition | |
| 1520 | V6 → 13.8%. Condenser(G1) peaks at 184 mbar. MC(H35) → 0.80 K. Still(P1) → 1.16 K / 2.0 mbar. |
| 1530 | V6 → 14.6%. Condenser(G1) peaks at 178 mbar. MC(H35) → 0.46 K. Still(P1) → 1.13 K / 1.1 mbar. |
| 1535 | V6 → 15.0%. Condenser(G1) peaks at 181 mbar. MC(H35) → 0.22 K. Still(P1) → 1.16 K / 0.55 mbar. |
| 1546 | Begin LHe transfer @ MB = 38.0% |
| starting transfer causes a bit of a rise in condenser and 1KPot | |
| 1555 | V6 → 100%. Condenser(G1) peaks at 159 mbar. MC(H35) → 0.14 K. Still(P1) → 1.05 K / 0.17 mbar. |
| 1600 | MC = 77 mK. Still = 1.09 K / 0.14 mbar. G1/G2 = 148/136 mbar. 1K Pot = 1.56 K / 11±1 mbar. |
| 1600 | Open V14 to pull the rest of the mixture out of the dump into circulation. Still peaks at 40 mbar, Condenser peaks at 192 mbar, MC peaks at 105 mK, then all relax again. 1K Pot unaffected. |
| 1625 | Still = 0.90 mbar. Close V14 |
| 1630 | End LHe transfer @ MB = 93.6% |
| 1635 | MC = 29.7 mK. Still = 1.09 K / 0.110 mbar. G1/G2 = 112/100 mbar. 1K Pot = 1.56 K / 11±1 mbar. |
| 1640 | Plug in DCRCs 1&3 and start DAQ programs |
| 1650 | had a bit of trouble starting a run and keeping the DAQ programs from crashing. Wound up powercycling the DCRCs, got it to work. |