2010/11/15
| 1217 | Pump out exchange gas, pump mixture into dump. MC T=78.1K |
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| 1339 | Throughput test at 77K 16mbar/min, about half of the value in the past. No leak at background level 4.3E-9 cc/s |
| 1356 | Do the throughput test again: 17mbar/min. Still too low. Pump mixture out. Probably the mixture was not cleaned well. We'll go ahead and blow out liquid N2 and clean the mixture at the same time and redo the throughput test after that. |
| 1411 | G1 always goes up to ~100mbar after V5 is closed. It doesn't seen V12B is leaking. Not sure what happened. |
| 1419 | Start to blow out liquid N2. He background 6.4E-9 cc/s |
| Cryoclean mixture | |
| 1530 | Liquid N2 is out. No gross leak found. |
| 1550 | Previous settings may not work. Try new settings and redo the cleaning |
| Cryocleanning settings |
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| 1659 | Stop cryocleaning mixture, pump mixture into dump. |
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| 1732 | Redo the throughput test after cleaning the mixture: 30mbar/min. The mixture was dirty. Pump out mixture. |
| 1734 | Pump the main bath. |
| 1745 | Leak level drops from ~1E-6cc/s to 3E-8cc/s when pumping the main bath. There is likely a leak. |
| 1746 | P2 reaches 1 mbar. Stop pumping bath and fill in He again |
| 1820 | Filled bath with He gas. Leak: 1.6E-6cc/s |
| Put in 0.1mbar He-4 exchange gas into IVC. (1mbar in exchange gas manifold → 0.063 mbar in IVC) | |
| 1852 | Pump transfer stick |
| 1917 | Pump He transfer stick to 5E-3cc/s |
| Transfer liquid He to 35.1%. Start pumping exchange gas at 20K, MC temperature starts to rise from 15K. Pump the exchange gas overnight |