2022/10/27 (Thursday)
- Lab in-personnel: Zach
| 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 thresholds: 7.0 - 11.0 MeV |
| Cooled to base two days ago after seventeenth 5K pumpout. | |
| Taking -80V NaI-triggered data overnight. | |
| 0915 | DCRC1pA baseline = -0.792 V |
| 0915 | Start -82.0 V PuBe data series 44 min long, SiHV-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC1pB threshold 10. Start series with the Start Button |
| 0915 | HV = -91.7 V, Vtest = -21.9 mV, Ileak = -24.1 uA, Vdet = -82 V (89%). |
| 0920 | MC base = 30.0 mK. Most spikes peaking below 33 mK, some above 35 mK |
| 0959 | Start -82.0 V PuBe data series 366 min long, NaI-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC4pA threshold 20. Start series with the Start Button |
| 1325 | HV = -91.7 V, Vtest = -22 mV, Ileak = -24.2 uA, Vdet = -82.1 V (89%). |
| 1330 | DCRC1pA baseline = -0.794 V |
| 1354 | MC/Coldplate = 30.2/151 mK, Still = 1.12 K / 0.065 mbar / 0 mW, G1/G2 = 125/113 mbar, 1K Pot = 45° / 1.58 K / 10±1 mbar, MB = 26.5% |
| MB relatively low, will have to do an early transfer tomorrow, maybe 9am | |
| 1354 | Fill LN2 cold trap dewar |
| 1609 | Dial HV down to 0V |
| 1611 | Close V6 to stop circulation. |
| 1616 | V6 is now fully closed (light is off on IGH, Still pressure is rising, Condenser pressure falling). Turn off 3He pump |
| 1617 | Close 1K Pot needle valve |
| 1618 | Open V3 to let mixture from Condenser side into Still side. |
| 1622 | MC = 0.42 K |
| 1622 | Turn on Still and MC heaters to 20 mW each |
| 1623 | Turn off DAQ programs and unplug DCRCs 1&3 |
| 1631 | 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. |
| 1650 | MC/1KPot = 3.20/3.07 K |
| 1655 | Check pressure in IVC: 0.012 ubar, it reads 1.2e-5mbar, it must be low because of the new fast warmup procedure? Start pumping out IVC with turbo pump |
| 1725 | MC/1KPot = 3.93/3.94 K. G1(fridge) = 805 mbar |
| 1735 | G1(fridge) = 840 mbar. Open V9 to release pressure into the dump. |
| 1755 | MC temp start rising more quickly |
| 1937 | Tower = 10.01 K. Turn off MC and Still heaters. |