| Status: | LN in MB. IVC turbo pumping overnight. |
| 1000 | IVC = 3.4 e-6mbar pumping, 40 e-6mbar with pump valved out |
| 1005 | LD = 0.44 e-9mbarL/s. Open LD to IVC, LD = 360 e-9mbarL/s and falling |
| 1030 | Begin blowing out LN. G3 → 225 mbar. LD = 240 e-9 mbarL/s |
| 1035 | G3 drops to 150 mbar. Maybe LN already mostly gone. |
| 1050 | Stop LN blowout. Only gas coming out of tube into the bomb Dewar. LD = 240 e-9mbarL/s |
| 1055 | Start pumping out MB with scroll pump. LD rises to 560 e-9mbarL/s. This rise is normal. |
| 1100 | P2 (MB) = 0.28 mbar. LD falling now, 540 e-9mbarL/s |
| 1110 | Fill MB with He gas |
| 1130 | Put 4.6e-2 mbar He exchange gas into IVC. MC and Sorb temperatures increase. |
| 1140 | Check 1K Pot pressure: 26 mbar on P2. Evacuate 1K Pot |
| 1200 | Begin LHe transfer. |
| 1200 | MC = 94 K, Sorb = 206 K |
| 1210 | Begin pressurizing Dewar for transfer. Note 250L Dewar began with only 173 L, but probably this is sufficient. |
| 1215 | Sorb temperature starts to decrease, peaked at 208 K |
| 1225 | MC = 98 K and flat, Sorb = 203 K |
| 1240 | Tried turning on 3He pump - light goes on on GHS but pump does not turn on. Is circuit box switched off?? |
| 1245 | MC = 92 K, Sorb = 160 K, IVC = 1.4e-2 mbar |
| 1250 | Reset pump power switchbox. On the box all the lights were off. I pressed the red button, Mains On, then the DC Fail light came on. Then I hit the white Reset button and the DC Fail light went off. Then I turned on the pump and it worked. |
| 1300 | With MC at 82 K perform throughput test. Unfortunately it looks like we have a blockage. G1 falls to 6.5 mbar and remains flat (zero throughput). |
| 1320 | MC = 71 K, Sorb = 79 K, IVC = 8.6e-3 mbar |
| 1330 | After pumping all mix to dump, perform another throughput test. MC = 67 K. G1 falls to 14 mbar barely rises over period of 5 minutes. Throughput ~ 0.3 mbar/minute. Blockage. |
| | we really should a) pump fridge out before LN transfer and b) clean mixture before throughput test |
| 1340 | Stop LHe transfer. (Never should have started it.) Level still too low to register. Leaving MB-side of transfer stick in MB - maybe Taconis will boil off the LHe faster. |
| 1345 | MC = 60 K, Sorb = 20 K, IVC = 1.0e-2 mbar |
| 1410 | MC = 51 K, Sorb = 19 K (but now rising, hit a minimum of 16 K |
| 1415 | Fridge contents pumped to dump, down to P1 = 0.7 mbar, G1 = 2 mbar. Turn off 3He pump. |
| note | I also pumped out LN2 Trap 1 and then put it in the LN2 Cold Trap Bath and filled the bath. |