2022/09/30 (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 source in storage in PAN443. |
| NaI trigger window: 7.6-11.2 MeV | |
| Cooled to base three days ago after tenth 5K pumpout. Taking SiHV-triggered -80V background data with low trigger overnight | |
| 1000 | Last night's data shows a decrease in dump sizes which is an indicator of when the helium films started killing the TES sensitivity.  At first dump sizes rose, maybe indicating increasing noise. Then around 10:30pm they started to fall. That's around dump 350 |
| MC temperature pattern is a bit different. An increase in baseline from 29.4→29.8 mK around 9:30 pm, then another increase from 29.8→30.4 around 2:20 am. The change in dump sizes occurred between these two time points. | |
| 1000 | Phonon baselines are high, DCRC1pA/B/D/DCRC3pA/B/C = -0.711/-0.665/-0.698/-0.638/-0.614/-0.668. Note that they are highest for the outer-ring channels (DCRC3pA&B) |
| 1000 | HV = -92.9 V, Vtest = -22.5 mV, Ileak = -24.7 uA, Vdet = -83 V (89%). |
| 1020 | Dial HV down to 0V |
| 1020 | Close V6 to stop circulation |
| 1030 | Turn off 3He pump |
| 1205 | Close 1K Pot needle valve |
| 1215 | Open V3; G1 falls, so this let mixture from Condenser side over to Still side. |
| 1220 | 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. |
| 1220 | Turn on Still and MC heaters to 20 mW each |
| 1330 | G1(fridge) = 840 mbar. Open V9 to release mixture into dump. |
| 1420 | MC reaches 5.78 K and is flat. |
| 1500 | Sorb reaches 7.5 K, flat. |
| 1510 | 1K Pot reaches 6.0 K, still rising but only slowly. |
| 1520 | Wedge a a layer of two washers between the knurled knobs of the stripline elbow on the side near the center of the fridge. I think this is about as far up as it will go. |
| 1525 | Turn off DAQ programs and unplug DCRCs 1&3 |
| 1525 | Check pressure in IVC: 0.14 ubar. A bit higher this time… |
| 1525 | Star pumping out IVC with turbo pump |
| 1535 | Fill LN2 cold trap bath |
| 1539 | Begin LHe transfer @ MB = 31.2% |
| 1555 | Bring PuBe source from storage in PAN443 back to its standard position in the K100 lab PAN43, behind the lead wall on the West side of the lead/poly shield. |
| 1625 | End LHe transfer @ MB = 94.6% |
| 1715 | MC/1Kpot/Sorb = 10.00/5.97/7.5 K Turn off MC and Still heaters |