| | Status: warming. All mixture in dump. LN2 traps warm, not pumped out. Mixture recovered from fridge while still below 10K so we should check LHe trap for H2 contamination and pump this out to air. |
| 0625 | MC(Cernox) = 186 K. By Newton's law of cooling/warming, at this rate should reach 50 Fahrenheit late tomorrow night (Monday 2 Oct). Could put more exchange gas (N2) into cryostat jacket to maybe warm more quickly. |
| 1300 | MC(Cernox) = 217 K. |
| 1320 | Close off recovery meter. Record recovery meter value. |
| 1335 | Add 5 3m hose-lengths of N2 gas into cryostat vacuum jacket |
| 1345 | Open LN2 Cold Trap 1 to G1. 58 mbar of contaminants. Pump this out with scroll pump. |
| 1355 | Open LHe trap to G1 by opening V1 with condenser valve closed. About 4 mbar rise on G1. This might be H2. Pump this out with scroll pump. (Actually G1 was still open to LN2 Cold Trap 1 by mistake, so that pressure also reflects the volume in that trap, not just the LHe trap.) |
| 1400 | Open still gate valve to see if there's any contaminants in fridge. P1 goes up about 0.6 mbar. Pump out fridge on both sides with scroll pump. |
| 1420 | Close still gate valve, condenser valve, and valves 1, 3, 5, 7, 5A, 2A. P1 = 0.55 mbar. G1/G2 = 1.3/548 mbar. P2 before closing valves = 0.02 mbar, after closing valves = 80.0 mbar. |
| 1420 | Turn off scroll pump. |
| 1505 | MC(Cernox) = 228 K. |
| 1700 | MC(Cernox) = 237 K. Rate of approach to room temperature is definitely higher now than before adding the N2, with a tau of 13.7 hours instead of previously 19.3 hours. Now the ETA for hitting 50 Fahrenheit is tomorrow at 13:00. |