2020/10/01 (Thursday)
- Lab in-person: Michael, later Matt
- Virtual partner: Matt, later Zach
| 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 off. Lead/poly shield erected (4 lead walls, 2 poly walls). |
|---|---|
| Status | Warming up to deal with clogged 1K Pot. Mixture in dump, helium in IVC, nitrogen in CVJ. MC/Still heaters = 20/30 mW. 1K Pot needle valve open to MB. |
| 0830 | MC(Cernox) = 199.8 K. Rising 2.8 K/hour At this warming rate, we will reach 253 K tomorrow around 11am (this is the temperature at which we tested 1K Pot throughput before; that time the Pot worked fine). We'll reach 273 K on Saturday morning. |
| 0930 | Michael's Body Temp = 98.6F |
| 1048 | Michael enters lab. |
| 1126 | Let 25 mbar N2 gas into vacuum manifold. Then open cryostat vacuum jacket valve to let this into the vacuum jacket. Vacuum Jacket → 1.2 mbar. |
| 1133 | Cryostat vacuum jacket 0.86 mbar |
| 1133 | Close CVJ port valve. |
| 1143 | Michael leaves lab |
| 1415 | MC(Cernox) = 216.3 K. Rising 3.6 K/hour Looks like it's warming faster now. Should reach 253 K tomorrow around 4am, 273 K tomorrow around 5pm. |
| 1630 | MC(Cernox) = 224.0 K. Rising 3.4 K/hour |
| 1750 | Matt enters lab |
| 1755 | Close 1K Pot needle valve, then pump out 1K Pot with Scroll Pump |
| 1800 | Pump out MB with Scroll Pump, down to < 5 mbar. Then pressurize MB with helium, to 240 mbar+1atm |
| 1810 | Perform 1K Pot throughput test (at MC = 229.5 K). Close needle valve then pump out 1K Pot, isolated from MB. MB is full of helium gas. Pump out 1K Pot, then stop pumping and watch the pressure rise at P2. Then repeat, but after stopping pumping open the needle valve a certain amount. Measured the amount of time to rise from one pressure to another. At needle valve = 0/10/20/30/60°, pressure change 0.1→0.2/0.3→1.0/0.3→1.5/0.3→1.5/1.0→5.0, risetime = 34/54/55/47/23 seconds. 0/10/20/30/60° → 0.18/0.78/1.3/1.5/10 mbar/min |
| 1820 | Close 1K Pot needle valve, pump out 1K Pot, close speedivalve. We'll leave it pumped out. |
| 1825 | Matt leaves lab |
| 1930 | MC(Cernox) = 233.8 K. Rising 3.3 K/hour. Predict 273 K tomorrow before 2 pm |
Todo list for the next few days (Matt out of town):
- After MC reaches 273 K, start pumping out the Cryostat Vacuum Jacket. We'll need to start with the Scroll Pump, then switch to the Turbo Pump at <0.1 mbar. Let it pump overnight at least.
- Turn off MC&Still heaters
- After pumping out the CVJ, pump out the IVC. Use Scroll Pump to pump out line to IVC valves first, and we'll probably need to start with the Scroll Pump on the IVC too. At <0.1 mbar switch to Turbo Pump. Let it pump overnight at least.