2022/09/23 (Friday)
- 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 West side of lead/poly shield. |
| NaI trigger window: 7.6-11.2 MeV | |
| Warmed up yesterday for ninth 5K pumpout. Turbo pumping IVC overnight. | |
| 1205 | MC/1KPot/Sorb = 5.40/6.57/8.30 K. G1(fridge) = 545 mbar |
| 1205 | Turbo on IVC = 1.2 nbar. With Turbo valved out for 1 minute IVC = 12 nbar. |
| 1210 | Close IVC valves on top of fridge |
| 1210 | 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 = 0.25 bar on mechanical gauge. |
| 1210 | 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). |
| 1215 | Start pumping 1K Pot continuously |
| 1215 | MC/1KPot/Sorb = 5.40/3.37/4.2 K. |
| 1235 | MC falls quickly… |
| 1235 | MC/1KPot/Sorb = 3.44/3.22/4.0 K. G1(fridge) = 470 mbar |
| 1310 | MC/1KPot/Sorb = 3.24/2.88/4.0 K. G1(fridge) = 374 mbar |
| 1310 | 1K Pot = 0° / 2.88 K / 2.6 mbar |
| 1310 | Open 1K Pot needle valve → 15°. 1K Pot → 2.57 K / 6.0 mbar |
| 1310 | MC = 3.15 K. G1(fridge) = 335 mbar |
| 1315 | Open 1K Pot needle valve → 30°. 1K Pot → 2.33 K / 8.0 mbar |
| 1325 | MC = 2.99 K. G1(fridge) = 278 mbar |
| 1325 | Open 1K Pot needle valve → 45°. 1K Pot → 2.10 K / 13 mbar |
| 1350 | Fill LN2 cold trap bath |
| 1400 | Some kinks in the MC cooling curve around 2.1 K, around the helium lambda point. |
| 1410 | Remove PuBe source from PAN43 K100 lab and put in storage in PAN443. We'll take data without the source this weekend to better understand the calibration and the NaI-coincident spectrum. |
| 1415 | MC = 2.08 K. G1(fridge) = 55 mbar. These are both flattening. |
| 1420 | Sudden drop in MC from 2.08 to 1.99 K, maybe that's the lambda point. |
| 1420 | 1K Pot = 1.54 K / 7.0 mbar, kinda low. Last time though it went up at some point, we'll try starting circulation. |
| 1420 | Close V3 and V9, leaving 49 mbar mixture in dump (G2) |
| 1420 | Turn on 3He pump. G1(condenser) → 57 mbar. |
| 1430 | Start circulation through Trap 1. V6 → 12.6%. Condenser peaks at 310 mbar. MC(H35) → 1.41 K. Still → 1.44 K / 26 mbar. |
| 1K Pot → 1.60 K / 14 mbar, better. | |
| 1435 | V6 → 13.0%. Condenser(G1) peaks at 236 mbar. MC(H35) → 1.15 K. Still(P1) → 1.19 K / 5.5 mbar. |
| MC wiggles around 1.2 K, Al Tc. | |
| 1450 | V6 → 13.4%. Condenser(G1) peaks at 194 mbar. MC(H35) → 1.08 K. Still(P1) → 1.18 K / 3.6 mbar. |
| 1500 | V6 → 13.8%. Condenser(G1) peaks at 176 mbar. MC(H35) → 0.72 K. Still(P1) → 1.16 K / 2.4 mbar. |
| 1505 | V6 → 14.4%. Condenser(G1) peaks at 179 mbar. MC(H35) → 0.42 K. Still(P1) → 1.14 K / 1.10 mbar. |
| 1515 | V6 → 15.0%. Condenser(G1) peaks at 177 mbar. MC(H35) → 0.20 K. Still(P1) → 1.15 K / 0.45 mbar. |
| 1525 | V6 → 100%. Condenser(G1) peaks at 161 mbar. MC(H35) → 56 mK. Still(P1) → 1.11 K / 0.10 mbar. |
| 1550 | MC = 33.6 mK. Condenser(G1) = 121 mbar. Still = 0.075 mbar. |
| 1555 | Accidentally open V4 instead of V14. That let some mix from the Condenser into the Dump. Close V4. |
| 1555 | Open V14 to pull the rest of the mixture out of the dump into circulation. MC peaks at 98 mK, Still peaks at 260 mbar, Condenser peaks at 203 mbar, then all relax again. 1K Pot unaffected. |
| 1615 | Still = 0.85 mbar. Close V14 |
| 1625 | MC = 31.7 mK and cooling |
| 1635 | MC = 28.9 mK |
| 1635 | Plug in DCRCs 1&3 |
| Starting the DAQ programs didn't work as usual - the DAQ programs started without shutting themselves off even with all DCRCs enabled, that's not the usual behavior. But I couldn't start a series without a crash. Wound up restarting MIDAS, now it's working ok. | |
| 1700 | Check phonon channels. They look good. Baselines still near -0.8 V except DCRC3pD, had to adjust its offset from 1.37 to 1.65 |
| 1700 | NaI is still triggering without the PuBe, rate is not severely reduced. We'll see when we take data. |
| 1705 | Fine tune offsets to get baselines close to -0.80 V |
| 1705 | MC = 29.4 mK. Seems to have settled here after turning on the DCRCs. |
| 1709 | Start 0 V bg 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 |
| 1746 | Start 0 V bg data series ## min long, NaI-triggered, with 1000 initial randoms, 5 Hz in-run randoms, trigger on DCRC4pA threshold 20. Start series with the Start Button |