2022/10/21 (Friday)
- 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 source behind lead wall on West side of lead/poly shield. |
| NaI trigger window: 7.6-11.0 MeV | |
| Cooled to base two days ago after fifteenth 5K pumpout. | |
| Taking NaI-triggered data overnight | |
| 0950 | DCRC1pA baseline: -0.823 V |
| 1001 | Start -82.3 V PuBe data series 84 min long, SiHV-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC1pB threshold 10. Start series with the Start Button |
| 1005 | MC base = 30.2 mK. Most spikes peak below 33 mK, some above 36 mK |
| 1005 | HV = -91.7 V, Vtest = -21.2 mV, Ileak = -23.3 uA, Vdet = -82.3 V (90%). |
| 1126 | Start -82.4 V PuBe data series 368 min long, NaI-triggered with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC4pA threshold 20. Start series with the Start Button |
| 1145 | DCRC1pA baseline: -0.823 V |
| 1145 | HV = -91.7 V, Vtest = -21.2 mV, Ileak = -23.3 uA, Vdet = -82.4 V (90%). |
| 1411 | MC/Coldplate = 30.3/149 mK, Still = 1.09 K / 0.090 mbar / 0 mW, G1/G2 = 103/114 mbar, 1K Pot = 45° / 1.58 K / 10±1 mbar, MB = 33.8% |
| 1412 | Fill LN2 cold trap bath |
| 1620 | DCRC1pA baseline: -0.822 V |
| 1620 | MC base = 30.1 mK. |
| 1730 | DCRC1pA baseline: -0.816 V. MC base has risen a little, from about 30.1 to 30.4 mK. Could be the first signs of helium films. |
| 1740 | Dial HV down to 0V |
| 1746 | Close V6 to stop circulation. |
| 1750 | V6 is now fully closed (light is off on IGH, Still pressure is rising, Condenser pressure falling). Turn off 3He pump |
| 1752 | Close 1K Pot needle valve |
| 1753 | Open V3 to let mixture from Condenser side into Still side. |
| 1754 | MC = 0.28 K |
| 1755 | Turn on Still and MC heaters to 20 mW each |
| 1756 | Turn off DAQ programs and unplug DCRCs 1&3 |
| 1605 | Move PuBe source out of K100 lab into storage (Howitzer in PAN434) |
| 1810 | Start NaI spectrum scan, 0-12 MeV step 0.05 MeV, 12 minutes per step. Should end around 9pm tomorrow. |
| 1812 | 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. |
| 1820 | MC/1KPot = 2.93/3.03 K |
| 1824 | Check pressure in IVC: 0.12 ubar. Start pumping out IVC with turbo pump |
| 1850 | MC/1KPot = 3.87/3.88 K. G1(fridge) = 760 mbar |
| 1900 | G1(fridge) = 789 mbar. Open V9 to release pressure into the dump. |
| 2135 | Tower = 11.05 K. Turn off MC and Still heaters, a little late (meant to do it at 10 K) |