2016/07/20 (Wednesday)
| Setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55(1)/33(2)/50(3) | |
| DCRCs on overnight. Note: fridge was cooled below Al transition with mu-metal shield lowered 27.7 cm. Cf source on fridge for overnight activation. | |
| 0645 | Tower/MC/Coldplate = 35.0/30.9/153 mK, Still = 1.30 K / 0.095 mbar, G1/G2 = 175/165 mbar, 1K Pot = 1.46 K / 2.4 mbar. MB = 39.8% |
| Tower temperature very stable overnight. MC(H35) may be lower, resistance continued to increase during measurement, got tired of waiting. | |
| Boiloff note: rate still looks good, suggests no taconis | |
| 0655 | Fill LN2 cold trap bath. |
| 0655 | Close V6 to begin warming above Al transition. |
| 0700 | Close V13a, turn off 3He pump, set MC heater to 1 mW |
| 0705 | Tower = 0.41 K and rising, G1(condenser) 75 mbar and falling, P1 (still) 50 mbar and rising, G2(pump outlet) 109 mbar and flat. |
| 0705 | Remove Cf source from fridge and return to safe. |
| 0710 | Lower mu-metal shield to 32.3 cm below standard position |
| 0715 | Tower = 0.67 K and rising, G1(condenser) 34 mbar and falling, P1 (still) 110 mbar and rising. Open V3. G1 falls to 17 mbar, P1 rises to 400 mbar. |
| 0740 | Tower reaches 1.4 K then suddenly jumps up to 3.2 K. (MC(Cernox) = 2.76 K.) G1 jumps from 20 mbar to 180 mbar and there's a surge in the 1K Pot. |
| 0750 | Turn off MC heater. Turn on 3He pump, open V13a, close V3. |
| 0755 | G1/G2 = 165/150 mbar. Start opening V6 to begin circulation. At 13.4% a response is seen, G1/G2 go up. |
| 0820 | At 8:10 1K Pot temperature shoots up to 3K, I think it ran dry. G1/G2 increase to near 700 mbar. Tweak open needle valve, 1K Pot and G1/G2 come back down. |
| 0825 | V6 = 13.6%, G1/G2 = 595/550 mbar and falling, 1K Pot = 1.71 K / 38 mbar. Tower = 1.85 K |
| 0835 | V6 = 13.8%. Tower/MC(H35)/Coldplate = 1.52/1.69/2.13 K, G1/G2 = 410/380 mbar and falling. P1(still) = 110 mbar. |
| 0850 | V6 = 14.5%. Tower/MC(H35)/Coldplate = 1.14/1.21/1.12 K, G1/G2 = 400/370 mbar and falling. P1(still) = 2.4 mbar. |
| 0900 | Open V6 100% |
| 0905 | Tower/MC(H35)/Coldplate = 0.37/0.29/0.32 K, G1/G2 = 325/300 mbar and flat. P1(still) = 0.17 mbar. |
| 0915 | Tower/MC(H35)/Coldplate = 87/69/177 mK, G1/G2 = 285/260 mbar and falling. P1(still) = 0.12 mbar. |
| 0950 | Tower/MC(H35)/Coldplate = 39.6/30.2/157 mK, G1/G2 = 195/180 mbar and flat. P1(still) = 0.075 mbar. |
| 0955 | Raise mu-metal shield to standard position |
| 1020 | Tower/MC/Coldplate = 36.0/28.6/154 mK, Still = 1.34 K / 0.070 mbar, G1/G2 = 185/175 mbar, 1K Pot = 1.54 K / 5.0 mbar. MB = 34.5% |
| 1035 | Adjust Driver Offsets to bring all pulses into range. Start a 30min background series at -4/+4 V with FG=5/2/5, OG=8/3/8, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown between series. Trigger on DIB1 phA with threshold of 30ADC bins, with 150 us pileup cut window. |
| 1140 | Check all the phonon channels, pulses look good. Looks like the timing link wasn't active for the last run. Manually start timing link. Take a test series. Note: DCRCs were disabled and reenabled with MIDAS for the HPGe run. Maybe this knocks out the timing link. |
| 1145 | Looking at raw pulses from this test it looks like the timing link is working again. |
| 1145 | Start a 30min background series at -4/+4 V with FG=5/2/5, OG=8/3/8, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown between series. Trigger on DIB1 phA with threshold of 30ADC bins, with 150 us pileup cut window. |
| 1245 | Power outage. Both pumps fail, circulation ceases, 1K Pot ceases cooling. Cannot restart the pumps, presumably building 3-phase power has stopped. Looks like it began around 1203. |
| Still pressure went up at 12:03, so this must be when pumps stopped. Tower temperature began to increase at 12:04. | |
| 1250 | Tower temperature has risen to 755mK and is rising. 1K Pot is at 4.0K/1000mbar. P1 has risen to 1000mbar, but G1/G2 are stable around 35mbar. Open V3 to equalize pressures between both sides of fridge. Close V13A to stop any circulation that might be happening. We'll just be mimicking the temporary warmup (though w/o the 1K Pot). |
| 1303 | Commence LHe transfer (29.6%). |
| 1315 | Tried just pushing the Mains On and Reset buttons, then starting the pumps. Pumps went on, power is back. Turn on 1K Pot. |
| 1325 | 1K Pot pressure is reading 1000 mbar (lowish still on the mechanical gauge at least). Close the needle valve a bit. Falls to 1.74 K / 80 mbar, stabilizing. |
| 1330 | Restart circulation (V3 closed, V13a&V12a&V1 open, 3He pump on, start opening V6). AT V6 = 13.4% circulation pressures increase. (G1/G2 were down to about 40 mbar so probably there is a lot of mix in the dump. Or, maybe not? Not sure whether anyone released mix to the dump when the power outage was discovered. Actually Allison says they did, and at 12:48 there were small changes in pressures, G1=31→30 mbar, G2=34→37 mbar.) |
| 1339 | End LHe transfer at 92.8% |
| Tower temperature peaked at 0.83 K at 13:15. Hopefully this is accurate so that the Al didn't go normal, because we want the flux locked in from when the shield was lowered (because we need to retake that data). For good measure, lower the shield to 32.3 cm now before cooling further. (Already the tower is down to 0.72 K after getting the 1K Pot started. | |
| 1345 | V6 = 13.4%, Tower = 0.72 K, G1/G2 = 90/85 mbar and falling, 1K Pot = 1.62 K / 15 mbar. |
| 1347 | Open port to allow pressure out of the main bath (8 minutes since the transfer ended). |
| 1355 | V6 = 13.6%, Tower = 0.64 K, G1/G2 = 150/135 mbar and flat, P1 = 34 mbar |
| 1400 | V6 = 13.8%, Tower = 0.61 K, G1/G2 = 165/155 mbar and flat, P1 = 6.0 mbar |
| 1410 | Open port to allow pressure out of the main bath (30 minutes since the transfer ended). |
| 1410 | V6 = 14.0%, Tower = 0.59 K, G1/G2 = 185/175 mbar and flattish, P1 = 4.5 mbar |
| 1420 | V6 = 14.2%, Tower = 0.59 K, G1/G2 = 220/205 mbar and flattish, P1 = 4.0 mbar |
| 1430 | V6 = 15.0%, Tower = 0.53 K, G1/G2 = 260/245 mbar and flattish, P1 = 1.3 mbar |
| 1439 | Open port to allow pressure out of the main bath (60 minutes since the transfer ended). |
| 1440 | V6 = 17.6%, Tower = 0.18 K, G1/G2 = 260/245 mbar and falling, P1 = 0.32 mbar, 1K Pot = 1.52 K / 5 mbar. Open V6 100%. |
| 1500 | Tower/MC/Coldplate = 40.0/33.2/154 mK, Still = 1.30 K / 0.110 mbar, G1/G2 = 100/185 mbar, 1K Pot = 1.50 K / 4.5 mbar. |
| 1510 | At base now. Mu-metal shield back in standard position. Start a 30min background series at -4/+4 V with FG=5/2/5, OG=8/3/8, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown between series. Trigger on DIB1 phA with threshold of 30ADC bins, with 150 us pileup cut window. |
| 1610 | Sequence finished. All pulses still look good. Start a 30min background series at -4/+4 V with FG=5/2/5, OG=8/3/8, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown between series. Trigger on DIB1 phA with threshold of 30ADC bins, with 150 us pileup cut window. |
| 1615 | Fill LN2 cold trap full. |
| P2: 1.8mbar. Open 1K Pot needle valve 16th of a turn. | |
| 1650 | P2 has settled at 6mbar. Open 1K Pot needle valve another 16th of a turn. |
| 1708 | Sequence finished. All pulses still look good. Start 13 hours of 30min Ba series at -4/+4 V with FG=5/2/5, OG=8/3/8, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown between series. Trigger on DIB1 phA with threshold of 30ADC bins, with 150 us pileup cut window. |
| 1730 | Placed Ba source on fridge at top of mu metal shield. |