2022/09/26 (Monday)
- Lab in-personnel: Matt
| Status | Run 76 in progress |
|---|---|
| Setup | Cables 2/3/1 → diverter/nothing/nothing → Side2-readout HV CONN 1/3/2 → HV 1(L)/2(R) → DCRC50(3)/DCRC55(1), DCRC33(2)→HV control, NaI trigger signal → DCRCX(4) Lead/poly shield fully assembled. Boron-filled socks covering NaI detectors. PuBe source in storage in PAN443. |
| NaI trigger window: 7.6-11.2 MeV | |
| Cooled to base three days ago after ninth 5K pumpout. Took -82.5V data overnight. | |
| 0905 | Check phonon channels: no pulses, elevated baselines, most above -0.7 V |
| 0910 | Dial HV down to 0V |
| 0920 | Phonon baselines for DCRC1pA,B,D,DCRC3pA,B,D = -0.725, -0.682, -0.711, -0.648, -0.618, -0.679 V = Side2pC,F,E,B,A,D |
| MC baseline temperature overnight: began around 29.5 mK, @ 19:30: 29.9 mK, @ 24:15: 30.2 mK, @ 1:55: 30.6 mK, @ 8:10: 31.0 mK | |
| 0925 | Close V6 to stop circulation |
| 0935 | Turn off 3He pump |
| 0940 | Open V3; G1 falls, so this let mixture from Condenser side over to Still side. |
| 1230 | Close 1K Pot needle valve |
| 1250 | 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. |
| 1250 | Turn off DAQ programs and unplug DCRCs 1&3 |
| 1255 | Turn on Still and MC heaters to 20 mW each |
| 1410 | G1(fridge) = 855 mbar. Open V9 to release mixture into dump. |
| 1500 | MC/1Kpot/Sorb = 5.77/4.37/5.5 K and pretty flat |
| 1505 | Check pressure in IVC: 0.10 ubar. |
| 1515 | Wedge a couple of washers between the knurled knobs of the stripline elbow on the side near the center of the fridge. |
| 1515 | Star pumping out IVC with turbo pump |
| 1527 | Begin LHe transfer @ MB = 33.4% |
| 1622 | End LHe transfer @ MB = 95.5% |
| 1650 | Fill LN2 cold trap bath |
| 1705 | MC/1Kpot/Sorb = 10.1/5.25/6.6 K Turn off MC and Still heaters |