2022/11/26 (Saturday)
- 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-seventh 5K pumpout. Turbopumping IVC overnight. | |
| 1005 | Take LN2 dewar to be filled |
| 1029 | Begin LHe transfer @ MB = 7.8% (forgot to update this before starting the transfer, so it might be a bit lower) |
| Also started the camera a little late, I estimated its starting value with a quick calculation of the rate. | |
| 1034 | Turbo on IVC = 0.74 nbar. With Turbo valved out for 1 minute IVC = 6.3 nbar. |
| 1036 | Close IVC valves at top of fridge. |
| 1050 | MB = 27.8% |
| 1055 | 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 = 0.47 bar on mechanical gauge. |
| 1058 | 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. |
| 1101 | 4He pump valve open all the way. |
| 1103 | 1K Pot = 3.18 K / 2.6 mbar. G1 (fridge+dump)=416 mbar. MC = 5.70 K. |
| 1105 | Forgot to open recovery to 4He pump before, just did |
| 1115 | Bring LN2 dewar back, fill cold trap dewar |
| 1121 | 1K Pot = 3.05 K / 2.4 mbar. G1 (fridge+dump)=382 mbar. MC = 3.28 K. |
| 1122 | Open 1K Pot needle valve → 15°. 1K Pot → 2.88 K / 5.5 mbar |
| 1127 | Open 1K Pot needle valve → 30°. 1K Pot → 2.75 K / 6.5 mbar |
| 1129 | Ended LHe transfer @ MB = 95.5% |
| 1132 | Open 1K Pot needle valve → 45°. 1K Pot → 2.55 K / 9.5 mbar |
| 1153 | Set up N2 purge |
| 1330 | MC/Still/1KPot = 1.73/1.76/1.52. G1(fridge+dump) = 35 mbar, flattening. |
| 1330 | Close V3 and V9, leaving 44 mbar mixture in dump (G2) |
| 1330 | Turn on 3He pump. G1(condenser) → 43 mbar |
| 1335 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 196 mbar. MC(H35) → 1.39 K. Still → 1.40 K / 20 mbar |
| 1340 | V6 → 13.0%. Condenser(G1) peaks at 195 mbar. MC(H35) → 1.24 K. Still(P1) → 1.25 K / 6.5 mbar. |
| 1345 | V6 → 13.4%. Condenser(G1) peaks at 181 mbar. MC(H35) → 1.07 K. Still(P1) → 1.00 K / 1.4 mbar. |
| 1350 | V6 → 13.8%. Condenser(G1) → 155 mbar, doesn't peak. MC(H35) → 1.04 K. Still(P1) → 0.94 K / 0.6 mbar. |
| 1355 | V6 → 14.4%. Condenser(G1) peaks at 128 mbar (then again at 131 mbar after passing through the Al transition). MC(H35) → 1.02 K. Still(P1) → 0.92 K / 0.4 mbar. |
| 1400 | V6 → 15.0%. Condenser(G1) peaks at 130 mbar. MC(H35) → 0.68 K. Still(P1) → 0.88 K / 0.32 mbar. |
| 1410 | V6 → 100.%. Condenser(G1) peaks at 134 mbar. MC(H35) → 0.58 mK. Still(P1) → 0.85 K / 0.090 mbar. |
| 1420 | Open V14 to pull the rest of the mixture out of the dump into circulation. Still peaks at 32 mbar, Condenser peaks at 181 mbar, MC peaks at 0.47 K, then all relax again. 1KPot = 1.56 K / 9.5±0.5 mbar. |
| 1440 | Still = 0.85 mbar. Close V14 |
| 1440 | MC = 0.12 K |
| 1500 | MC = 54 mK |
| 1720 | MC = 29.1 mK |