2022/11/16 (Wednesday)
- 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 behind lead wall on W side of fridge. NaI array trigger window = 4.73 - 5.13 MeV |
| Cooled down two days ago after twenty-third 5K pumpout. Taking -82V data overnight with NaI window around 5 MeV | |
| 1000 | HV = -90.8 V, Vtest = -21 mV, Ileak = -23.1 uA, Vdet = -81.6 V (90%). |
| 1000 | DCRC1pA baseline = -0.790 V |
| 1000 | MC base = 29.6 mK with most spikes peaking below 33 mK, some above 34 mK |
| 1003 | Start -81.6 V PuBe data series ## min long, SiHV-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC1pB threshold 10. Start series with the Start Button |
| 1048 | Start -81.7 V PuBe data series ## good min long, NaI-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC4pA threshold 20. Start series with the Start Button |
| 1135 | DCRC1pA baseline = -0.783 V |
| 1135 | MC/Coldplate = 30.0/151 mK, Still = 1.13 K / 0.100 mbar / 0 mW, G1/G2 = 141/128 mbar, 1K Pot = 60° / 1.58 K / 11.5±0.5 mbar, MB = 33.2% |
| 1140 | Fill LN2 cold trap bath |
| 1335 | DCRC1pA baseline = -0.742 V. Clearly elevated - He films are now messing up the phonon channels. Time to warm up. |
| 1345 | Dial HV down to 0V |
| 1350 | Turn off DAQ programs. Also stop MIDAS on cdms1 so we can test it on cdms2 |
| 1355 | Close V6 to stop circulation. |
| 1400 | V6 is now fully closed (light is off on IGH, Still pressure is rising, Condenser pressure falling). Turn off 3He pump |
| 1400 | Open V3 to let mixture from Condenser side into Still side. |
| 1400 | Close 1K Pot needle valve |
| 1405 | MC = 0.38 K |
| 1405 | Turn on Still and MC heaters to 20 mW each |
| 1435 | 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. |
| 1510 | MC/1KPot = 3.86/3.99 K. G1(fridge) = 748 mbar. |
| 1510 | Open V9 to release pressure into the dump. |
| 1525 | MC/1KPot = 6.17/6.37 K, flat |
| 1525 | Check pressure in IVC: 0.086 ubar, strangely low. Start pumping out IVC with turbo pump. |
| 1525 | MB = 25.9% |
| 1900 | Tower = 10.01 K. Turn off MC and Still heaters |