2016/09/14 (Wednesday)
| Status: fridge at room temperature, cryostat Dewar is down, tower installed, turbopumping IVC overnight. Mixture is in dump and 3He pump, manual dump valves are closed. |
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| 0830 | Turbo pressure = 74 nbar, IVC = 8.6 μbar. Better than Run 59, a bit worse than the first Run 60 setup. |
| 0835 | Switch on leak detector |
| 0855 | LN2 storage Dewar is empty, begin refilling it |
| 0910 | Retighten bottom and middle IVC flanges |
| 0920 | Start leak detector on IVC, valve out turbo pump. Initially background leak is around 80 pbarL/s. |
| 0930 | Leak settles around 96 pbarL/s, 10 times higher than Run 59, 4 times higher than the first Run 60 setup. |
| 0935 | Squirt-test all vacuum joints, no obvious increase in leak signal, remains around 97 pbarL/s. |
| 0940 | Close valves to IVC at top of fridge, leak falls to 9 pbarL/s |
| 0955 | Fill LN2 cold trap bath |
| 1020 | Start cryocleaning mixture through Trap 2. V6 is open to 12.5%. After a couple of minutes flow looks low, increase V6 to 12.9%. Now closing V13b shows clear increase on G2, mix is flowing. |
| 1030 | Squirt-test IVC vacuum joints, top and bottom, more carefully. No sign of leak, LD remains at around 100 pbarL/s |
| 1035 | Flow looked low again, open V6 to 13.1% to restore flow. |
| 1045 | Flow looked low again, open V6 to 13.2% to restore flow. |
| 1111 | Cleaning still shows flow. |
| 1125 | Stop cryocleaning. Pump mix out of Trap 2 into dump. |
| 1155 | G2 (dump) has flattened at 777.2 mbar. P1 also seems nearly flat at 28 μbar. Close all valves and turn off 3He pump. Remove Trap 2 from LN2 bath to let warm up. Pbarometric = 30.32 inHg, so adjusted Pdump = 790.7 mbar |
| 1200 | Open V12a plus speedivalve and V1. This opens the condenser line (and LHe trap) to LN2 Trap 1, in order to cryopump out any remaining air/water from its long exposure to atmosphere. |
| 1210 | G1 seems to have fallen from about 1.5 to 1.0 mbar. Open V3. Now the still pumping line is also open to Trap 1. P1 increases from 10 to 60 μbar, then falls a little. Settles at 50 μbar. |
| 1215 | Close V12a and speedivalve, then open Still gate valve and Condenser speedivalve. No change on P1 or G1. Re-open V12a and speedivalve. |
| 1220 | Stop pumping IVC with turbo pump and start pumping it with leak detector again. Leak signal settles at 104 pbarL/s. |
| 1225 | Turn on 3He pump then open V13a. This lets some mixture into the fridge. G1/G2 → 220 mbar. Watch leak signal. No increase in signal. |
| 1235 | Close V3, then open V6 to 13.0% to start flowing mixture through fridge in standard circulation path. We're cleaning a part of the mixture (most is still in the dump) through Trap 1 and flowing it through the fridge. The idea is to sorta flush out any remaining water in fridge lines. G1/G2 → 410/365 mbar. |
| 1240 | Increase V6 to 13.2% |
| 1302 | Put transfer stick back on IVC, vacuum inner main bath and raise dewar. |
| 1315 | Close V13A to check for flow. Open V6 to 13.4%. Flow restored. |
| 1320 | Close V13A. We still have flow. Open V9 to begin pumping mixture to dump through fridge. G1 reads 504mbar and dropping. Open V6 all the way to speed this process. |
| 1328 | G1 = 498.9mbar. So there's definitely flow. Open up V5 to pump from both sides of the fridge. |
| 1340 | The entire time the leak rate stays at 103 pbarL/s. No sign of leak from fridge lines to IVC. |
| 1345 | Begin pumping on Main Bath with scroll pump. |
| 1350 | Flushed main bath with He gas, pumped out 1K pot. Them, after closing 1K pot speedivalve, briefly open 1K pot needle valve to flush 1K pot with He gas. |
| 1400 | Commence LN2 transfer. |
| 1402 | Cease leak checking on IVC, add 5.4 mbar N2 exchange gas. |
| 1410 | Trap 2 is at room temperature, open it up to G2: 46 mbar of contaminants from last cleaning. Pump out the trap using the 4He pump. Return Trap 2 to LN2 bath. |
| 1430 | Fridge is cooling. MC (Cernox) = 263 K, IVC = 3.4 mbar |
| 1456 | Take test data series with DCRC 1 (Stripline 27 - Readout side) and DCRC 3 (Stripline 20 - Bias side) with no voltage applied for 2000 randoms. This series is for practicing proper contact free data processing. |
| 1500 | MC (Cernox) = 183 K, IVC = 2.5 mbar |
| 1505 | Begin cryocleaning mixture through LN2 Cold Trap 1. Open V6 to 12.9% to begin flow. |
| 1515 | Increase V6 to 13.2% |
| 1530 | MC (Cernox) = 142 K, IVC = 2.2 mbar |
| Increase V6 to 13.3% | |
| 1540 | MC (Cernox) = 133 K, IVC = 2.2 mbar, Sorb = 180 K (down from its 250 K max) |
| 1557 | End LN2 transfer. Fridge temperature at 123 K and IVC pressure at 1.9 mbar. |
| 1655 | Increase V6 to 13.4% |
| 1700 | MC (Cernox) = 101 K, IVC = 1.9 mbar, Sorb = 124 K |
| 1715 | MC (Cernox) = 97 K, IVC = 1.6 mbar, Sorb = 123 K. Cease cryocleaning and pump mixture to dump. |
| 1752 | MC (Cernox) = 91K, IVC = 1.6 mbar. Start pumping out IVC exchange gas with scroll pump. Close V6. |
| 1755 | Switch to pumping on IVC with trubo pump. |
| 1756 | V6 closed. Isolate dump (G2=780 mbar) by closing all valves on IGH and closing coldtrap 1 speedivalve. Turn off pump. |
| 1759 | Remove coldtrap 1 from LN2 bath and open to P2, which had a starting pressure of 0.26 mbar. |
| 1805 | Leave with MC (Cernox) = 91 K, IVC = 7.4e-6 mbar, and P2 = 5.0 mbar (and probably still rising). |