| 1000 | Perform mixture throughput test at MC = 208 K using above procedure. Let G1 rise to 570 mbar before Step 3, then it falls to 37 mbar, then begins to rise. Throughput 7.3 mbar/min. |
| | Looks like the blockage is gone, though we are well below freezing, at least at the MC. Sorb on the other hand has been above 250 K since late last night. So possibly the still level is above freezing already, hard to say, it would be a little surprising. |
| | Throughput about the same as the room-temperature test on 18 Sep, worse than the 280 K test on 29 June. Should be better than either of these, so maybe a little bit of a blockage still there. But pressure differential is a little smaller now than in those last two tests. |
| 1010 | Pump mixture from fridge and LN2 Trap 2 back to dump |
| 1015 | MC(Cernox) = 210.2 K |
| 1035 | Begin cryocleaning mixture through cold LN2 Trap 2, V6 = 12.9% |
| 1040 | Increase V6→13.2% to reestablish flow |
| 1115 | Increase V6→13.3% to reestablish flow |
| 1145 | Stop cryocleaning mixture, pump mixture back to dump |
| 1155 | warm LN2 Trap 1 = 15.1 mbar. Pump out with scroll pump. |
| 1210 | Begin cryocleaning mixture through cold LN2 Trap 1, V6 = 12.7% |
| 1220 | Increase V6→13.1% to reestablish flow |
| 1220 | MC(Cernox) = 220.8 K, cryostat outer surface = 21.3 C |
| 1320 | Stop cryocleaning mixture, pump mixture back to dump |
| 1345 | warm LN2 Trap 2 = 9.7 mbar. Pump out with scroll pump. |
| 1405 | Begin cryocleaning mixture through cold LN2 Trap 2, V6 = 12.9% |
| 1410 | Increase V6→13.1% to reestablish flow |
| 1515 | Stop cryocleaning mixture, pump mixture back to dump |
| 1520 | MC(Cernox) = 233.9 K, cryostat outer surface = 21.5 C |
| 1540 | warm LN2 Trap 1 = 4.3 mbar. Pump out with scroll pump. |
| 1710 | warm LN2 Trap 2 = 3.2 mbar. Pump out with scroll pump. |
| 1715 | MC(Cernox) = 241.1 K, cryostat outer surface = 21.6 C |
| | should reach 273 K by about 7am |
| 1730 | Open dump to cold LN2 Trap 2 to let mixture cryoclean over the weekend |