| 1100 | Fill N2 cold trap full. |
| | Open valve V6 to 13.8% and continue to cryoclean mixture. |
| 1500 | Pump mixture into dump. |
| 1530 | Throughput test yields some improvement… perhaps I am fooling myself, but the intial throughput rate seems higher than it was yesterday. Perhaps the mixture was very dirty (G2 pressure is 25 mbar lower than yesterday at 662 mbar… hopefully this doesn't mean that we have lost some mixture!). It might be worth cleaning the N2 cold traps again and cryocleaning overnight. |
| | Pump mixture into dump. |
| 1700 | Open valves 8, 11A & 11B to remove mixture from N2 cold traps. |
| 1800 | Pumping the mixture out of the N2 cold traps is taking ages. P1 reads 0.026 mbar; equilibrium value is 0.012 mbar so there is still some mixture present. Perhaps some air in the cold traps is boiling off and contributing. Close speedivalve on condenser line and fill N2 cold trap full. |
| | G1 is hovering at 0.9 mbar… can't explain why it isn't zero. |
| 1900 | Ensuring N2 cold trap is full has no effect. Perhaps this is just natural outgassing, and there is no mixture left in the cold traps. |
| | Isolate and remove cold traps from LN2 bath. Leave to warm naturally to room temperature. Open vent and monitor pressure rise on P2: pressure increases to 1000 mbar! Looks like they were heavily contaminated. Mixture might need more cleaning. Evacuate line until pressure reaches 0.5 mbar, and then switch pump off. Pressure on P2 increases to 1000 mbar again! Keep He-4 pump on. |
| 2100 | Switch off He-4 pump. Pressure in P2 rises to 5 mbar. |
| | Expose N2 cold traps to heat gun periodically for 1 hour. |
| 2200 | Pressure in P2 rises to 35 mbar. Turn on He-4 pump. |