| Status | Run 77 beginning, initial LHe transfer yesterday, mixture in fridge with 3He pump off |
| 1200 | MC(Cernox)/Sorb/1K Pot = 4.74/8.7/6.8 K, G1/G2 = 544/479 mbar, MB = 43.9% |
| | Yesterday before leaving P2 was creeping up, now it is maxed out at 1000 mbar, maybe there is a small leak somewhere? |
| 1205 | Turbo on IVC = 1.2 nbar. With Turbo valve out for 1 minute IVC = 14 nbar |
| 1208 | Fill LN2 cold trap bath |
| 1240 | Pump out line leading to 1K Pot with scroll pump (V4a open, 1kpot speedivalve closed). Then switch the line over to the 4He pump. Turn on 4He pump and make sure the pump exhaust is connected to recovery and open valve to recovery lines. |
| 1251 | After pumping out the lines, closing V4a caused P2 to rise to 5 mbar, why? Open up the 4He pump inlet valve to pump it out again with V4a closed |
| 1254 | Check pressure in 1K Pot by opening the 1kpot speedivalve with V4a closed: Mechanical gauge = 0.32 bar. |
| 1256 | Pump out 1K Pot by slowly opening V4a then the manual valve at the 4He pump until it just starts to make noise, once it quiets down somewhat open it up a little more. continue this until the valve is fully open. |
| | P2 read max at 1000 mbar after opening V4a (Corrected from previously stated as V1a). Opened the 4He pump valve until it was making a slight noise and P2 went down quickly, to 1 mbar, lower than normal, then I opened the valve all the way and no noise. Why is nothing making sense today? |
| 1300 | MC(Cernox)/Sorb/MC(H35) = 4.73/4.2/4.73, 1K Pot = 3.39 K / 1.0 mbar. G1 (fridge+dump) = 525 mbar. |
| | Leaving mixture in the fridge when starting 1K pot |
| 1313 | Open 1K Pot needle valve → 15° (half unit on the needle marks). 1K Pot → 2.88 K / 7 mbar. |
| 1317 | Open 1K Pot needle valve → 30°. 1K Pot → 2.25 K / 28 mbar. |
| 1320 | MC(H35) temp starts to decrease, flattens at around 3 K |
| 1325 | MC(Cernox)/Sorb/MC(H35) = 2.97/4.0/2.92, 1K Pot = 2.02 K / 28 mbar. G1 (fridge+dump) = 301 mbar. |
| 1340 | MC(H35)/Still/1KPot = 2.36/2.21/1.65 K / 22 mbar, G1(fridge+dump) = 99 mbar |
| 1345 | Try the new RoX thermometer, Tower(RoX) = 2.09K, back to the H35 = 2.16 K |
| 1350 | 1KPot = 12 mbar now, Open 1K Pot needle valve → 37°, no noticeable change. |
| 1352 | MC(H35) flattening at 2.11K, must be lambda point, Tower(RoX) = 1.99K, Tower(U28) = 2.05 |
| 1355 | 1KPot = 9,5 mbar now, Open 1K Pot needle valve → 45°, 1K Pot → 1.58 K / 11 mbar. |
| 1400 | P2 jumped up, didn't see how high it went, now is at 45mbar, close 1kpot needle valve by 15°, P2 drops to 17 mbar, 1kpot = 1.67 K |
| | P2 oscillating somewhat with needle valve at 30° |
| 1407 | P2 somewhat stable at 28 mbar again |
| 1433 | Start LHe transfer @ MB = 39.7% |
| 1437 | MC(H35)/Still/1KPot = 1.89/1.93/1.66 K / 30 mbar, G1(fridge+dump) = 50 mbar |
| 1442 | Close V3 and V9, leaving 28.8 mbar in the dump. Turn on 3He pump. |
| 1445 | Start circulation through Trap 1. V6 → 12.6%. P2 jumps up to max, stop circulation |
| 1447 | P2 now settled at 9.5 mbar. start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 118 mbar. MC(H35) → 1.42 K. 1kpot goes up to 34 mbar, then recovers to 24 mbar. P1 (still) → 20 mbar. |
| 1453 | V6 → 13.0%. Condenser(G1) peaks at 99 mbar. MC(H35) → 1.14 K. Still(P1) → 1.18 K / 5 mbar. |
| | MC(H35) flattens for a bit at 1.05K |
| 1457 | V6 → 13.4%. Condenser(G1) peaks at 101 mbar. MC(H35) → 1.07 K. Still(P1) → 1.14 K / 3.4 mbar. |
| 1500 | V6 → 13.8%. Condenser(G1) peaks at 108 mbar. MC(H35) → 0.86 K. Still(P1) → 1.11 K / 2.2 mbar. |
| 1504 | V6 → 14.4%. Condenser(G1) peaks at 109 mbar. MC(H35) → 0.72 K. Still(P1) → 1.09 K / 1.2 mbar. |
| 1508 | V6 → 15.0%. Condenser(G1) peaks at 108 mbar. MC(H35) → 0.47 K. Still(P1) → 1.08 K / 0.7 mbar. |
| 1512 | V6 → 100.%. Condenser(G1) peaks at 103 mbar. MC(H35) → 0.29 K. Still(P1) → 1.03 K / 0.24 mbar. |
| 1515 | Open 1K Pot needle valve → 37°. 1K Pot = 1.65 K / 38 mbar. |
| 1527 | Open 1K Pot needle valve → 45°. 1K Pot = 1.67 K / 45 mbar. |
| 1530 | MC(H35) = 41 mK, Still = 1.08 K /0.120 mbar, 1KPot = 1.67 K / 40 mbar, G1/G2 = 82/73 mbar |
| 1531 | Tower(U28) = 69.7 mK, Tower(RoX) = 82.3 mK |
| 1535 | Open V14 to let the remaining mix out of the dump and into circulation. P1(Still) peaks at 75 mbar then falls again. MC(H35) peaks at 83 mK. Condenser peaks at 109 mbar. |
| 1555 | Tower(RoX)/Tower(U28)/MC(H35)/Coldplate = 76.7/61.0/43.8/150 mK, Still(P1) = 1.09 K / 1.8 mbar / 0 mW, G1/G2 = 61.7/58.8 mbar, 1K Pot(P2) = 45° / 1.66 K / 38 mbar, MB = 92.1% |
| 1600 | Still (P1) < 1 mbar, close V14 |
| 1607 | Decrease the 1K Pot needle valve → 35°, P2 → 24 mbar, 1kpot = 1.62K |
| 1631 | Tower(RoX)/Tower(U28)/MC(H35)/Coldplate = 70.0/54.0/30.9/145 mK, Still(P1) = 1.09 K / 0.11 mbar / 0 mW, G1/G2 = 70.0/60.5 mbar, 1K Pot(P2) = 35° / 1.62 K / 24 mbar, MB = 91.1% |
| 1647 | Tower(RoX)/Tower(U28)/MC(H35)/Coldplate = 70.0/53.7/30.7/145 mK, Still(P1) = 1.09 K / 0.11 mbar / 0 mW, G1/G2 = 70.0/61.0 mbar, 1K Pot(P2) = 35° / 1.62 K / 24 mbar, MB = 91.0% |