2022/09/18 (Sunday)
- Lab in-personnel: Matt, Giulia
| 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 | |
| Cooled to base a couple days ago after seventh 5K pumpout. | |
| Taking -80V data overnight. DAQ crash at 2:30 am, no data after that. | |
| 1145 | As of this morning I can't log into cdms1. So we can't access/restart the DAQ. |
| 1435 | Figured out how to reduce the bias to 0 without the DAQ: telnet commands to DCRC2. See setting_up_dcrc_boards. Also see RevC.0 Register Map. Connected from cdms3 with telnet 128.101.21.162 5001. Did rd 5A (qI charge bias) - this was 3289. Doing wr 5A 3290 caused the HV to drop. So I stepped this up manually (in hexadecimal); at 3A55 I got the HV down to -12 mV |
| 1545 | MC/Coldplate = 29.4/150 mK, Still = 1.12 K / 0.075 mbar / 0 mW, G1/G2 = 130/128 mbar, 1K Pot = 45° / 1.59 K / 13±1 mbar |
| By now or soon helium films will kill the phonon channels, so let's go ahead and start warming up. | |
| 1550 | Close V6 to stop circulation. |
| 1555 | Turn off 3He pump |
| 1615 | Close 1K Pot needle valve |
| 1630 | Turn on Still and MC heaters to 20 mW each |
| 1644 | Begin LHe transfer @ MB = 29.3% |
| 1655 | Unplug DCRCs 1&3 |
| 1700 | Fill LN2 cold trap bath |
| 1700 | 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. |
| 1700 | Open V3; G1 rises, so apparently Still side was at higher pressure than Condenser side. |
| 1731 | End LHe transfer @ MB = 95.7% |
| 1750 | MC/1Kpot = 3.87/4.23 K and rising. Fridge (G1) = 755 mbar and rising |
| 1750 | Open V9 to release mixture into dump. MC temperature drops, then starts rising again |
| 1815 | MC reaches 3.5 K then starts rising much faster |
| 1940 | MC/1Kpot/Sorb = 6.26/4.33/5.4 K and flat |
| 1940 | Check pressure in IVC: 0.086 ubar. Star pumping out IVC with turbo pump |
| MC temperature starts rising again | |
| 2120 | MC = 10.0 K. Turn off MC and Still heaters |