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| | Setup: DIB1/3/4 → 3.2 MHz filters 3/1/2 → cable 3/1/2 →gender changer 3/1/2 → HVConn 1/3/2 → HV 1/2 → DCRC55/DCRC33 |
| 0905 | Tower = 33.6 mK, Main Bath = 30.8%. Boil off rate: faster than slow mode (predicted level: 34.0%) |
| 0910 | Fill LN2 cold trap bath. |
| 1100 | Start LHe transfer (MB = 27.7%)
note: this was an attempt at a slow transfer, with low pressurization. |
| 1115 | Tower/MC/Coldplate = 33.7/31.5/190 mK, Still = 1.2 K / 0.120 mbar, G1/G2 = 244/217 mbar, 1K Pot = 1.697 K / 32 mbar. |
Initial pressurization: 1.0 PSI. Fill started out very slowly. Recovery meter rate was around 4 cuft/min, typically it's 6 or 7
At around 1pm we started recording data:
| time | Main Bath (%) | reco rate (cuft/min) |
| 13:09 | 43.8 | 4.9 |
| 13:21 | 47.0 | 4.8 |
| 13:45 | 54.1 | 4.7 |
| 14:05 | 56.9 | 4.8 |
| 14:39 | 67.1 | 4.8 |
| increase pressurization from 1.25 to 1.5 PSI |
| 15:17 | 93.3 | 6.1 |
| 1520 | End LHe transfer with 94.2%. |
After calculating the final values for the transfer, we found that much more LHe had been removed from the storage Dewar than normal: 77 L, typical for a fill is 40-45 L. The overall recovery rate was about the same as usual, no improvement.
| time | Main bath | recovery (cuft) |
| No Dewar on recovery |
| 01:23 | | 31420 |
| 02:55 | | 31440 |
| 04:26 | | 31460 |
| 05:58 | | 31480 |
| 07:33 | | 31500 |
| 09:05 | 30.8% | 31520 |
| 10:37 | | 31540 |
| 1715 | Fill LN2 cold trap bath. |
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