2020/09/24 (Thursday)
- Lab in-person: Matt
- Virtual partner: Zach, Ruiren
| Setup | Run 73. DIB 1/3/4 → Stripline 43/48/41 → pi-filters 1/2/3 → Cable 3/1/2 → nothing/nothing/accessory_interposer → HV_Conn 1/3/2 → HV 1/2 → DCRCX(4)/DCRC55(1)-master; DCRC33(2) → HV control. DCRCs on. Lead/poly shield erected (4 lead walls, 2 poly walls). |
|---|---|
| Status | Doing a partial warming to get helium out of the IVC. Circulation and 1K Pot stopped. Helium exchange gas in IVC (no gas in cryostat vacuum jacket). MC and Still heaters on and LEDs on to help warm up tower. Bath is slowly boiling away. 1K Pot speedivalve and needle valve open |
| 0016 | MB = 11%, Recovery = 383907.6 / 16.3 cuft/hr |
| 0116 | MB = 9.5%, Recovery = 383923.9 / 16.3 cuft/hr |
| 0216 | MB = 8.1%, Recovery = 383940.2 / 16.3 cuft/hr |
| 0316 | MB = 6.7%, Recovery = 383956.4 / 16.2 cuft/hr |
| 0416 | MB = 5.3%, Recovery = 383972.7 / 16.4 cuft/hr |
| 0516 | MB = 3.9%, Recovery = 383989 / 16.3 cuft/hr |
| 0616 | MB = 2.5%, Recovery = 384005.3 / 16.3 cuft/hr |
| 0716 | MB = 1.2%, Recovery = 384021.6 / 16.3 cuft/hr |
| 0816 | MB = 0.1%, Recovery = 384037.7 / 16 cuft/hr |
| 0916 | MB = -0.7%, Recovery = 384054.3 / 16.7 cuft/hr |
| 1016 | MB = -1.0%(minimum reading), Recovery = 384070.8 / 16.4 cuft/hr |
| 1116 | Recovery = 384088.3 / 17.5 cuft/hr |
| 1216 | Recovery = 384105.1 / 16.8 cuft/hr |
| 1035 | MC(Cernox)/1K Pot/Sorb = 4.90/5.24/6.6 K, G1(fridge+dump) = 582 mbar. Temperatures were pretty flat through the night but now rising. |
| 1116 | Recovery = 384088.3 / 17.5 cuft/hr |
| 1216 | Recovery = 384105.6 / 17.3 cuft/hr |
| 1245 | MC(Cernox)/1K Pot/Sorb = 5.08/5.77/7.3 K, G1(fridge+dump) = 587 mbar. |
| 1316 | Recovery = 384122 / 16.4 cuft/hr |
| 1416 | Recovery = 384138.3 / 16.3 cuft/hr |
| 1400 | MC(Cernox)/1K Pot/Sorb = 5.15/6.03/7.6 K, G1(fridge+dump) = 589 mbar. |
| 1435 | Matt arrives in lab |
| 1440 | IVC = 2.5 ubar. Yesterday Zach left it at 1.6 ubar. |
| 1450 | Begin pumping out IVC with Turbo Pump. After a minute or so, can see acceleration in the warming of MC and 1K Pot. |
| 1500 | Matt Fritts body temperature = 98.1 F |
| 1500 | MC(Cernox)/1K Pot/Sorb = 5.41/6.64/8.5 K, all rising. G1(fridge+dump) = 592 mbar. |
| 1516 | Recovery = 384153.9 / 15.6 cuft/hr |
| 1530 | Fill LN2 cold trap bath |
| 1540 | MC(Cernox)/1K Pot/Sorb = 7.18/>7/11.7 K. G1(fridge+dump) = 581 mbar (it fell a little after the LN2 fill). |
| 1545 | Matt leaves lab |
| 1615 | MC(Cernox)/Sorb = 8.69/13.4 K. |
| 1616 | Recovery = 384169 / 15.1 cuft/hr |
| 1710 | MC(Cernox)/Sorb = 12.6/16.4 K. This is about as warm as we got to for the last partial warmup, which was successful. But this time the IVC walls are still cold because there is still LHe in the MB. |
| 1715 | Turn off LEDs. This does not seem to slow the warming much. We'll leave them off. Change width/rate from current settings (500/1000 us) to standard settings (100/10000 us). |
| 1720 | MC = 13.1 K. Turn off MC&Still Heaters. MC temperature levels out. |
| 1716 | Recovery = 384183.8 / 14.9 cuft/hr |
| 1735 | MC(Cernox)/Sorb = 12.9/16.2 K. Now that heaters are off these are falling. Interesting that Sorb is affected, somehow MC or Still heater was warming it as well. |
| 1810 | MC(Cernox)/Sorb = 12.9/16.0 K. They're mostly flat now. |
| 1816 | Recovery = 384198.4 / 14.5 cuft/hr |
| 1916 | Recovery = 384212.5 / 14.1 cuft/hr |
| 2016 | Recovery = 384226 / 13.5 cuft/hr |
| 2116 | Recovery = 384239.1 / 13 cuft/hr |
| 2145 | MC(Cernox)/Sorb = 13.2/22.8 K. Now rising. |
| 2216 | Recovery = 384251.3 / 12.3 cuft/hr |
| 2316 | Recovery = 384262.6 / 11.3 cuft/hr |