2023/02/25 (Saturday)
* Lab in-personnel: Zach
| Begin another cooldown | |
| 1412 | Begin LHe transfer @ MB = 32.7% |
| 1415 | Fill LN2 cold trap dewar |
| 1416 | Turn on 4He pump. Open Recovery valve to 4He pump. Pump out line to 1K pot (open V4a, close 1K pot speedivalve and slowly open the 4He-pump inlet valve).Close the 4He-pump inlet valve once done. Check pressure in 1K Pot (with V4a open, 4He pump inlet valve closed). 1K Pot = 0.28 bar (-21.5 inHg) on mechanical gauge. |
| 1418 | Pump out 1K Pot slowly, opening the 4He pump valve until it just starts to make noise, then opening it more when it becomes more quiet. |
| 1420 | Open 4He pump valve fully |
| 1421 | Turbo on IVC = 1 nbar, after being valved out for a min, IVC = 10 nbar, open turbo again and close valves to IVC |
| 1425 | MC(H35) = 5.36 K, cooling slowly. 1K Pot = 3.24 K / 3.0 mbar |
| 1426 | Open 1K Pot needle valve → 15° (half a unit mark). 1K Pot (P2) → 2.78 K / 9.5 mbar |
| 1430 | MC temp dropping |
| 1432 | MC(H35) = 3.31 K, Open 1K Pot needle valve → 30°. 1K Pot → 2.36 K / 19 mbar. |
| 1440 | Open 1K Pot needle valve → 45°. 1K Pot → 1.76 K / 34 mbar. |
| 1444 | MC(H35)/1Kpot = 2.84/1.70 K, MC temp dropping linearly. G1/G2 = 223/221 mbar . 1K Pot(P2) = 34 mbar, not very stable |
| 1455 | End LHe transfer @ MB = 95.0% |
| 1525 | MC(H35)/1Kpot = 2.07/1.65 K and flat. G1/G2 = 51.5/50.7 mbar . 1K Pot(P2) = 32 mbar. |
| 1525 | Close V3 and V9, leaving 50.7 mbar mixture in dump. Turn on 3He pump. |
| 1527 | Start circulation through Trap 1. V6 → 12.6%. Condenser(G1) peaks at 368 mbar. MC(H35) → 1.54 K. Still → 1.61 K / 40 mbar. |
| 1537 | V6 → 13.0%. Condenser(G1) peaks at 251 mbar. MC(H35) → 1.27 K. Still(P1) → 1.29 K / 6.5 mbar. |
| 1542 | V6 → 13.4%. Condenser(G1) peaks at 239 mbar. MC(H35) → 1.16 K. Still(P1) → 1.20 K / 3.6 mbar. |
| 1547 | V6 → 13.8%. Condenser(G1) peaks at 239 mbar. MC(H35) → 1.18 K. Still(P1) → 1.17 K / 2.4 mbar. |
| 1552 | V6 → 14.4%. Condenser(G1) peaks at 252 mbar. MC(H35) → 0.82 K. Still(P1) → 1.12 K / 1.5 mbar. |
| 1557 | V6 → 15.0%. Condenser(G1) peaks at 257 mbar. MC(H35) → 0.63 K. Still(P1) → 1.11 K / 0.85 mbar. |
| 1606 | V6 → 100.%. Condenser(G1) peaks at 259 mbar. MC(H35) → 0.23 K. Still(P1) → 1.06 K / 0.2 mbar. |
| 1635 | MC(H35) = 34.9 mK and pretty flat, G1 = 181.1 mbar and pretty flat. 1K Pot = 1.65 K / 34 mbar. |
| 1636 | Open V14 to pull the rest of the mixture out of the dump into circulation. |
| 1637 | MC(H35) rises to 81 mK, Still rises to 180 then falls again, Condenser(G1) rises to 268 mbar. 1K Pot unaffected. |
| 1659 | P1 = 0.85 mbar (<1), close V14 |
| 1700 | Plug in DCRCs, the timing setup seemed to be off, DCRC1 RX was connected to DCRC3 RX… Set it up as DCRC1 → DCRC3 → DCRC4 |
| Setup | Cable 2/1/3 → diverter/nothing/nothing → DCRC50(3)/DCRC55(1)/DCRCX(4) |