2022/09/16 (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 behind lead wall on West side of lead/poly shield. |
| NaI trigger window: 7.6-11.2 MeV | |
| Warmed up yesterday, seventh 5K pumpout. | |
| Cooling to base today | |
| 1222 | Turbo on IVC = 1.2 nbar. With Turbo valved out for 1 minute IVC = 12 nbar. |
| 1224 | Close IVC valves on top of fridge |
| 1225 | 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 = 0.23 bar on mechanical gauge. |
| 1230 | Pump out 1K Pot in stages, alternating 1K Pot Speedivalve and V4a, opening V4a in brief spurts to keep 4He pump pressure low (below 5 mbar). |
| 1240 | Start pumping 1K Pot continuously |
| 1240 | MC = 5.66 K, cooling slowly. 1K Pot = 3.37 K / 2.2 mbar, cooling slowly |
| 1245 | Open 1K Pot needle valve → 15°. 1K Pot → 3.06 K / 6.5 mbar |
| 1248 | Fill LN2 cold trap bath |
| 1250 | Open 1K Pot needle valve → 30°. 1K Pot → 2.93 K / 8.5 mbar |
| 1255 | Open 1K Pot needle valve → 45°. 1K Pot → 2.66 K / 13 mbar |
| 1257 | G1/G2 = 409/383 mbar dropping linearly |
| 1300 | MC/1Kpot = 3.25/2.43K dropping linearly |
| 1424 | Begin LHe transfer @ MB = 36.6% |
| 1428 | Close V3 and V9, leaving 49.5 mbar mixture in dump |
| 1428 | Turn on 3He pump |
| 1435 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 261 mbar. MC(H35) → 1.53 K. Still → 1.58 K / 50 mbar. |
| 1445 | V6 → 13.0%. Condenser(G1) peaks at 245 mbar. MC(H35) → 1.39 K. Still(P1) → 1.44 K / 20 mbar. |
| 1449 | P1 jumps for a moment, going over 30 mbar |
| 1455 | V6 → 13.4%. Condenser(G1) peaks at 221 mbar. MC(H35) → 1.19 K. Still(P1) → 1.20 K / 4.0 mbar. |
| 1505 | V6 → 13.8%. Condenser(G1) peaks at 188 mbar. MC(H35) → 0.99 K. Still(P1) → 1.13 K / 2.0 mbar. |
| 1507 | Ended LHe transfer @ MB = 94.5% |
| 1513 | G1 still rising slowly |
| 1515 | V6 → 14.4%. Condenser(G1) peaks at 200 mbar. MC(H35) → 0.63 K. Still(P1) → 1.12 K / 1.1 mbar. |
| 1525 | V6 → 15.0%. Condenser(G1) peaks at 190 mbar. MC(H35) → 0.30 K. Still(P1) → 1.14 K / 0.55 mbar. |
| 1535 | V6 → 100%. Condenser(G1) peaks at 182 mbar. MC(H35) → 0.14 K. Still(P1) → 1.08 K / 0.17 mbar. |
| 1540 | plug in DCRCs 1 and 3 |
| 1545 | MC = 64mK, G1 = 166mbar |
| 1650 | MC = 28.4 mK and pretty flat, Condenser = 129 and pretty flat. 1K Pot = 1.57 K / 12±1 mbar. |
| 1650 | Open V14 to pull the rest of the mixture out of the dump into circulation. |
| MC rises to 85 mK, Still peaks above 30 mbar then falls again, Condenser rises to 208 mbar. 1K Pot unaffected. | |
| as usual we'll wait till Still is below 1 mbar then close V14. | |
| 1715 | Still = 0.8 mbar. close V14 |
| 1930 | Swap HV leads to negative polarity |
| 2030 | Check phonon channels - three channels have shifted baselines. Relocking fixes two of them - had to adjust offset on DCRC1pA. Now all baselines close to -0.80 V |
| 2042 | Dial HV up to -109.25V nominal, -107.2V actual, for 15% prebias (using RootSequencer) |
| 2047 | Dial HV down to -95V nominal, -92.9V actual |
| 2050 | HV = -92.9 V, Vtest = -24.7 mV, Ileak = -27.2 uA, Vdet = -82 V (88%). A little worse than usual. Let's dial down to get Vdet up to 90% |
| 2053 | Dial HV down to -90V nominal, -88.0V actual |
| 2055 | HV = -88 V, Vtest = -19.5 mV, Ileak = -21.4 uA, Vdet = -79.4 V (90%). |
| 2059 | Start -79.4 V PuBe data series 59 min long, SiHV-triggered, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC1pB threshold 10. Start series with the Start Button |
| 2200 | Start -79.7 V PuBe data series 747 min long, NaI-triggered, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC4pA threshold 20. Start series with the Start Button |
| 2205 | HV = -88 V, Vtest = -18.9 mV, Ileak = -20.8 uA, Vdet = -79.7 V (91%). |