| | Status: Fridge blockage discovered yesterday, warming up. He gas in main bath vacuum jacket and in IVC. Small leak at top of stripline tube. Mixture is in dump, fridge evacuated. |
| 0910 | MC(Cernox) = 278 K, IVC = 5.4 mbar |
| 0920 | Check pressure in LHe trap on G1: about 0.8 mbar. Check pressure in condenser on G1: about 0.5 mbar. Check pressure in still on P1: no change, seems to be less than 0.1 mbar. Begin pumping out fridge lines with scroll pump, through v5a, v2a, v7, v2, v1, v8, condenser speedivalve, still gate valve. Pump for about 10 minutes. |
| 0935 | LN2 Trap 2 is warm, check pressure on G1: 84.5 mbar. Let this into the P2 volume, G1 falls to 33 mbar, P2 off scale. Pump out Trap 2 with scroll pump. |
| 1120 | Begin to pump out dewar jacket with scroll pump. Pressure read about 4 mbar before starting pump, including large bellows hose. |
| 1130 | Begin pumping on dewar jacket with turbo pump. |
| 1130 | Put Trap 2 back in LN2 bath, fill bath |
| 1145 | MC (Cernox) = 284 K. Pump out fridge lines with scroll pump for a few more minutes |
| 1150 | Turbo pump = 0.25 μbar, main bath vacuum jacket = 14 μbar |
| 1150 | Stop pumping out fridge with scroll pump, then open the fridge volume to LN2 Trap 1 to cryopump it a bit. |
| 1200 | Verify cross-channel resistances now that we are at room temperature again. All are around 10 kΩ, whether same-side or not, except DIB2 pD is open to other channels as it should be, this is the non-connected DIB channel. |
| 1205 | Fridge pressures have increased slightly, a few tenths of a mbar, since opening the fridge to Trap 1. Isolate Trap 1 again, then pump fridge with scroll pump a few more minutes, then isolate fridge and LHe trap. |
| 1205 | Turbo pump = 0.14 μbar, main bath vacuum jacket = 12 μbar |
| 1220 | Begin cryocleaning mixture through LN2 Trap 2 |
| 1235 | Pump out main bath and 1K Pot, then fill bath with He gas |
| 1240 | Turbo pump = 0.12 μbar, main bath vacuum jacket = 12 μbar. Stop pumping out vacuum jacket and reconnect pump manifold to IVC port. |
| 1300 | Let 4.6 mbar He exchange gas into IVC (adjustment from what was left in it yesterday) |
| 1305 | MC(Cernox) = 286 K. |
| 1305 | Begin LN2 transfer. |
| 1335 | MC(Cernox) = 280 K, Sorb > 249 K(max), IVC = 4.0 mbar. |
| 1400 | MC(Cernox) = 252 K, Sorb > 249 K(max), IVC = 3.4 mbar. |
| 1430 | MC(Cernox) = 216 K, Sorb > 249 K(max), IVC = 2.5 mbar. |
| 1530 | MC(Cernox) = 156 K, Sorb = 238 K, IVC = 2.2 mbar. |
| 1600 | MC(Cernox) = 135 K, Sorb = 182 K, IVC = 1.9 mbar. Level resistor = 1.307 kΩ |
| 1610 | Stop cryocleaning, pump mixture back to dump.
NOTE: trap2 is probably pretty dirty now. Should remove it and pump it out later. |
| 1630 | MC(Cernox) = 120 K, Sorb = 151 K, IVC = 1.9 mbar. Level resistor = 1.320 kΩ |