| 0100 | Raise dewar. IVC pressure 1.9E-4 mbar: a little high, but will have to suffice. Isolate turbo pump and open line to leak checker. Background helium leak rate 1.3E-8 mbar l/s: a little high, but low enough to conduct test. Evacuate 1 K pot. Evacuate main bath and overpressurise with He-4 gas. Helium leak rate rises to 4E-8 mbar l/s before falling again. Similar behaviour as the last couple of runs, so probably nothing to worry about. |
| 0115 | Dump pressure 681 mbar. Commence cryocleaning mixture through nitrogen cold trap 1. |
| 0120 | Fill IVC with 1 mbar He-4 exchange gas. Commence nitrogen transfer. |
| 0350 | Nitrogen liquid level meter reads 1.33 kΩ. Nitrogen transfer complete. Attach ping-pong ball. |
| 0455 | Fill N2 cold trap full. |
| 0950 | With mixing chamber temperature at 78.4 K and IVC pressure at 8.6E-1 mbar, begin pumping out exchange gas with rough pump. |
| 1005 | With IVC pressure at 4E-2 mbar, switch to turbo pump. |
| 1520 | With mixing chamber temperature of 77.8 K and IVC pressure of 2.5E-4 mbar begin open IVC to leak checker and isolate turbo pump. |
| 1540 | Leak checker stabilized to 1.6E-8 mbar*l/s background rate with IVC pressure of 4.6E-3 mbar. Begin Nitrogen blowout. |
| 1625 | Fill LN2 cold trap full. |
| 1710 | Nitrogen blow-out complete. Helium leak rate has risen to 1.2E-4 mbar l/s before we started to pump main bath. It looks like there is a gross leak in the bottom flange. Leak rate was still rising when we started to evacuate main bath. |
| 1740 | Fill main bath with He to attempt second leak check. Initial background rate 1.7E-7 mbar*l/s. As soon as He line was opened to main bath the leak rate rose to E-3 mbar*l/s and continued rising. This suggests (yet again) that there is a gross leak. Morale is low, riots expected. |
| 1800 | Lower dewar and fill IVC with 10 mbar Nitrogen exchange gas to aid in warm up. |