2022/11/14 (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 behind lead wall on W side of fridge. NaI array trigger window = 4.73 - 5.93 MeV |
| Warmed up yesterday for twenty-third 5K pumpout. Turbo pumping IVC overnight. | |
| 0932 | Begin LHe transfer @ MB = 3.6% |
| 0940 | Turbo on IVC = 0.86 nbar. With Turbo valved out for 1 minute IVC = 10 nbar. |
| 0940 | Close IVC valves at top of fridge. |
| 0945 | Fill LN2 cold trap bath |
| 0950 | Turn on 4He pump. Open Recovery valve to 4He pump. Pump out line to 1K pot (speedivalve closed). Check pressure in 1K Pot (with V4a open, 4He pump inlet valve closed). 1K Pot = 0.38 bar on mechanical gauge. |
| 0950 | Pump out 1K Pot slowly, throttling the flow at the valve at the pump inlet, opening just until the pump gets louder, then waiting, then opening a little more, etc. With pump just a little loud, can see pressure go down at the mechanical gauge. When this is low, open valve a bit more. When P2 gets below 30 mbar open valve all the way. |
| 0955 | 4He pump valve open all the way. |
| 0955 | 1K Pot = 3.18 K / 3.4 mbar. G1 (fridge+dump)=426 mbar. MC = 9.59 K. |
| MC didn't cool very much overnight after turning off the heaters this time. Hopefully this won't be a problem… | |
| 1010 | 1K Pot = 3.10 K / 3.4 mbar. G1 (fridge+dump)=396 mbar. MC = 9.15 K. |
| 1030 | 1K Pot = 2.99 K / 3.4 mbar. G1 (fridge+dump)=376 mbar. MC = 5.87 K. |
| 1030 | Open 1K Pot needle valve → 15°. 1K Pot → 2.89 K / 5.5 mbar |
| 1040 | MC = 3.26 K. G1(fridge+dump) = 373 mbar. |
| 1041 | End LHe transfer @ MB = 95.6% |
| 1055 | 1K Pot = 2.54 K / 5.7±0.3 mbar |
| 1055 | Open 1K Pot needle valve → 30°. 1K Pot → 2.37 K / 6.7±0.3 mbar |
| 1110 | Open 1K Pot needle valve → 45°. 1K Pot → 1.87 K / 9.5±0.5 mbar |
| 1120 | MC = 2.66 K. G1(fridge+dump) = 156 mbar. |
| 1125 | Open 1K Pot needle valve → 60°. 1K Pot → 1.71 K / 12 mbar |
| 1720 | MC/Still/1KPot = 1.68/1.73/1.59. G1(fridge+dump) = 32 mbar and flat. |
| 1725 | Close V3 and V9, leaving 23 mbar mixture in dump (G2) |
| 1725 | Turn on 3He pump. G1(condenser) → 38 mbar |
| 1725 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 250 mbar. MC(H35) → 1.40 K. Still → 1.45 K / 32 mbar |
| 1735 | V6 → 13.0%. Condenser(G1) peaks at 269 mbar. MC(H35) → 1.17 K. Still(P1) → 1.22 K / 4.5 mbar. |
| 1740 | V6 → 13.4%. Condenser(G1) peaks at 220 mbar. MC(H35) → 1.0 K. Still(P1) → 1.18 K / 3.0 mbar. |
| 1800 | V6 → 13.8%. Condenser(G1) peaks at 190 mbar. MC(H35) → 0.47 K. Still(P1) → 1.16 K / 1.8 mbar. |
| 1810 | V6 → 14.4%. Condenser(G1) peaks at 192 mbar. MC(H35) → 0.27 K. Still(P1) → 1.17 K / 0.8 mbar. |
| 1820 | V6 → 15.0%. Condenser(G1) peaks at 179 mbar. MC(H35) → 0.21 K. Still(P1) → 1.15 K / 0.55 mbar. |
| 1825 | V6 → 100.%. Condenser(G1) peaks at 182 mbar. MC(H35) → 93 mK. Still(P1) → 1.10 K / 0.16 mbar. |
| 1830 | Open V14 to pull the rest of the mixture out of the dump into circulation. Still peaks at 24 mbar, Condenser peaks at 204 mbar, MC peaks at 99 mK, then all relax again. 1K → 1.58 K / 12±1 mbar. |
| 1900 | Still = 0.55 mbar. Close V14 |
| 1905 | MC = 30.4 mK |
| 1930 | MC = 27.6 mK |
| 2010 | MC = 27.3 mK |
| 2025 | Plug in DCRCs 1&3 |
| 2030 | Check phonon channels. Relock and adjust some of the offsets to get baselines ~ -0.8 V |
| 2120 | Adjust phonon offsets to get all baselines near -0.800 V |
| 2120 | MC = 28.9 mK |
| 2127 | Dial HV up to -108.1V nominal, -106.2 V actual, for 15% prebias (using RootSequencer) |
| 2130 | Set NaI array trigger window to 4.73 - 5.13 MeV |
| 2133 | Dial HV down to -94V nominal, -91.9V actual |
| 2135 | Step HV down to -93V nominal, -90.8V actual |
| 2135 | HV = -90.8 V, Vtest = -20.6 mV, Ileak = -22.7 uA, Vdet = -81.8 V (90%). |
| 2140 | DCRC1pA baseline = -0.789 V |
| 2141 | Start -81.8 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 |
| 2220 | DCRC1pA baseline = -0.797 V |
| 2223 | Start -81.8 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 |