| | Begin another warm up and pump out (and fridge recovery) |
| 1039 | Close V6 to stop circulation. |
| 1042 | V6 is now fully closed (light is off on IGH, Still pressure is rising, Condenser pressure falling). Turn off 3He pump, leave 4He pump on until I arrive at lab |
| 1043 | Open V3 to let mixture from Condenser side into Still side. G1 and G2 drop to around 450 mbar. |
| 1124 | Close 1K Pot needle valve, P2 = 0.15 mbar now |
| 1125 | Close 1K Pot speedivalve, V4a, 4He pump inlet valve. Turn off 4He pump. Close recovery valve to 4He pump outlet. NOTE: remember to open recovery valve when the pump is turned back on. |
| 1126 | MC(H35) = 5.29 K, 1KPot > 7 K |
| 1127 | Turn off DAQ programs and unplug DCRCs 1,3,4 |
| 1128 | I do not know if there is any LHe left in the bath, the level is -1.0%, Since it is still hooked up to recovery I assume it is still filled with He gas. And Since the MC has not risen much above 5K it is still somewhat cold? I will not do any flushing or pumping and go straight to the LHe transfer |
| 1139 | Begin LHe transfer @ MB = -1.0% |
| | When taking out the stopper to the main bath, it seems the bath was still cold and pressurized, that is good. |
| 1142 | MC temp rising, now at 6.24 K |
| 1144 | MC temp now falling, at 5.34 K currently |
| 1145 | Fill LN2 cold trap bath |
| 1148 | 1KPot temp now reading, currently 5.4 K |
| 1154 | MC(H35)/1KPot = 4.39/3.57K, both stable |
| 1159 | MB = 44.9%, G1/G2 = 295/270 mbar. Everything has recovered, so I will continue the 10K pumpout procedure. |
| 1201 | Turn on Still and MC heaters to 20 mW each |
| 1206 | MC rose to 5.14 K and is flat now but G1/G2 are not rising |
| | Thinking about things, when I opened V3 earlier, G1/G2 were at 450 mbar but the MC was high at 5K, where normally the mixture would be at >800 mbar, this does not bode well |
| 1215 | Turn off MC and Still heaters |
| | I think I should pump the mixture to dump to make sure we still have it… |
| 1221 | Open V9 to let mixture into the dump |
| 1224 | G2 went up to 464 mbar, then settled, G1/G2 = 450/413 mbar now, still rising a bit |
| 1226 | Close V13a, turn on 3He pump, open V6→13.0%. This will start pumping from the fridge (both sides) and from cold LN2 Trap 1 into the dump. (V12a+speedi, V1, V3, V9 all already open) |
| 1229 | Ended LHe transfer @ MB = 92.3% |
| 1232 | Open V6 to 30% |
| 1236 | After pumping the mixture to the dump for some time, G2 = 713.6, it seems we didn't lose mixture. |
| | The GHS diagram shows some sort of connection between V3 and the dump (looks like a rectangle with a diagonal line through it), so I speculate that this is a pressure relief valve that let some of the mixture to dump when I opened V3 this morning |
| 1245 | G1/G2/P1 = 0.3/713.9/0.09 mbar, MC(H35)/1KPot = 4.29/4.25 K |
| 1247 | Stop pumping out fridge (close V1, V3, V6, then V9). G2(Dump) = 714.4 mbar |
| | Barometric pressure = 30.11“ (source is https://w1.weather.gov/data/obhistory/KMSP.html.) Corrected dump pressure = 720.8 mbar. |