2015/01/15
| 1030 | G1=1.7 mbar, P1=22 ubar, G2=0.9 mbar, with a fridge temperature of 78 K and the external pressure sensor reading 10 mbar. |
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| 1050 | Close all valves on IGH, isolate turbo pump and switch to scroll pump. Pump out He gas line. |
| 1100 | Fill LN2 cold trap full. Recommence pumping on fridge lines with turbo pump. Notice that G2 has risen to 5.2 mbar. |
| 1112 | G2 has dropped down to 3.4 mbar. |
| 1255 | Open V7, V11A, V12A, and V3 to let gas into still line. Noticed that G1 rose when opening V12A, indicating leftover gas/contaminate in cold trap. Commence pumping out cold trap. |
| 1305 | G1=1.4 mbar, P1=95 ubar, and G2=1.5 mbar. Let in gas to G1 and P1. G1 rises to 999.9 mbar and P1 rises to 1000 mbar. Close V3 and pump out G1 until it reads 1 mbar. Close V2, V7, and open V1. No immediate change. |
| 1316 | G1=14 mbar, P1=1000 mbar. |
| 1341 | It is noted that over 23 minutes (13:12 to 13:35) G1 rose from 10 mbar to 50 mbar. This flow rate of 1.7 mbar/min seems constant. Lower dewar and commence warm up process. Although G1 pressure indicates a slight “bump” in pressure at this time, it returns to the “normal” LN2 temperature flow rate of 1.7 mbar/min. |
| 1440 | Rate at which G1 was rising suddenly increases and then begins to flatline again. Mixing chamber temperature is around 110K. G1 rose from 89mbar (and a rate of ~0mbar/min) at 14:21 to G1=235 mbar at 14:30. Changes in pressure and temperature are recorded in the table below. P1 has not changed from 1000 mbar. |
| G1 (mbar) | Mixing chamber temperature (K) | |
|---|---|---|
| 14:21 | 89 | 107 |
| 14:22 | 140 | 108 |
| 14:23 | 175 | 110 |
| 14:24 | 195 | 112 |
| 14:25 | 205 | 113 |
| 14:26 | 215 | 114 |
| 14:27 | 225 | 115 |
| 14:30 | 235 | 120 |
| 1440 | A gap in temperature recorded by the DAQ appears at 14:39. This might be due to checking temperature values at the time in order to make the table above. |
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| 1605 | More rises in G1, documented in the table below. Currently a steady flow rate of roughly 70 mbar/min and a mixing chamber temperature of 213 K. |
| G1 (mbar) | Mixing chamber temperature (K) | |
|---|---|---|
| 15:30 | 252 | 188 |
| 15:38 | 252 | 195 |
| 15:39 | 275 (slight plateau here) | 195 |
| 15:40 | 275 | 196 |
| 15:41 | 285 | 196 |
| 15:42 | 291 | 197 |
| 15:43 | 294 | 198 |
| 15:44 | 295 (plateau) | 199 |
| 15:51 | 295 | 205 |
| 15:52 | 345 | 206 |
| 15:53 | 420 | 206 |
| 15:54 | 490 | 207 |
| 15:55 | 560 | 207 |
| 15:56 | 620 | 207 |
| 1610 | G1 reaches max value of 999.9 mbar. Fridge temperature currently at 213 K. Close V1 and open V2 to pump out G1. Once G1 reaches 0 mbar, close V2 and open V1. G1 jumps to 888 mbar and starts to decrease slowly. At 873 G1 starts to rise again, with a rate of roughly 40 mbar/minute. |
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| 1625 | G1 reaches max value of 999.9 mbar. Fridge temperature currently at 225 K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 862 mbar, with an increasing rate of 23 mbar/minute. |
| 1631 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 231K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 848mbar, with an increasing rate of 23 mbar/minute. |
| 1642 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 237K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 848mbar, with an increasing rate of 22 mbar/minute. |
| 1653 | Rate of G1 increase has slowed to ~8 mbar/min. |
| 1655 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 244K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 843mbar, with an increasing rate of 20 mbar/minute. |
| 1713 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 252K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 851mbar, with an increasing rate of 22 mbar/minute. |
| 1733 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 258K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 840mbar, with an increasing rate of 15 mbar/minute. |
| 1758 | G1 reaches max value of 999.9mbar. Fridge temperature currently at 266K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 839mbar, with an increasing rate of 16 mbar/minute. |
| Full warm up test | Zoom in of first spike | Zoom in of second spike |
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| 1822 | Mixing chamber has reached a temperature of 273 K. G1 currently at 993 mbar, with a flow rate of ~1 mbar/min. |
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| 1825 | G1 approaches its max value of 999.9mbar. Fridge temperature currently at 274K. Close V1 and open V2 to pump out G1. Once G1 reaches 1 mbar, close V2 and open V1. G1 settles at 834mbar, with an increasing rate of 12 mbar/minute. |
| 1843 | Mixing chamber temperature has reaches 277 K, with G1= 960 mbar and a flow rate of 3 mbar/min; end the test. P1 is still at 1000 mbar. Open V2 and V3 to commence pumping on fridge lines with scroll pump. |
| 1855 | Switch to turbo pumping on fridge lines. External pressure sensor reads 10 mbar. |