2018/09/14 (Friday)
| Setup: DIB1/3/4 → 3.2 MHz filters 2/3/1 → cable 3/1/2 → gender changer 3/?/2 → HVConn 1/3/2 → HV 1/2 → DCRC55(1)/DCRC50(3) 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V) / Ortec 575A(gain=10, shaping = 3us) → x10/x10 attenuator → DCRCX(4) DCRC33(2) → kepco 1kV power supply → HV input |
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| status: | Took 22Na data overnight at -80V. |
| 0910 | DCRC1pB is railed, re-lock it. |
| 0910 | Tower/MC/Coldplate = 31.8/30.4/192 mK, Still = 1.0 mW / 1.5±0.1 K / 0.090 mbar, G1/G2 = 119/113 mbar, 1K Pot = 1.60 K / 18 mbar, Turbo on IVC = 0.86 nbar, MB = 38.6% |
| 0915 | Fill LN2 cold trap bath. |
| 1113 | MIDAS sequence is stopped with error: Cannot start run: Cannot start run: or timeout froun: or timeout frover01' on host frover01' on host Run is stopped, -80V bias is applied still and DCRCdriver is not running. The last series on disk is at 1042. |
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Here are the relevant MIDAS errors. Maybe we momentarily lost connection to cdms2 for some reason and MIDAS panicked and killed the dcrc_driver01 process?
| 1120 | Restart DCRC programs and turn bias down to 0 using change_HV_80_to_0.msl |
|---|---|
| 1124 | Flash detector. |
| 1155 | Zap SQUIDs. |
| 1220 | After zap, base temperature has fallen to below the usual, down to 29.7 mK. (Maybe more Still heat would improve our base.) |
| 1230 | Return 22Na source too safe. |
| 1230 | Switch HV leads to be in +HV bias voltage configuration. |
| 1245 | Trying to get channels in transition and locked again after Zap. DCRCpC,D both keep losing lock and/or falling into SC. Probably need to adjust QET biases if we're going to continue to be at this lower base temp (currently 29.6 mK) |
| 1250 | Start test dataset at 0V, with CDMS and NaI detectors running and DCRC2 as HV controller. CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = 10 NaI detector: 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V, Pos) / Ortec 575A(gain=10, shaping = 3us, Pos) → x10/x10 attenuator → DCRC4PB/PA, Driver Gains = 1/1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 64 (64 samples) 1000 BOR randoms, trigger on DCRC3pB/C/D threshold = 7/10/9 |
| 1253 | Turn up HV prebias to 46V using change_HV_0_to_40_preBias_15_5_DCRC2.msl |
| 1257 | Monitoring pulses using SQUIDTuningGUI. DCRC3pC keeps jumping lock back and forth> I'll keep chasing it, but it will probably be railed for a good portion of this data. |
| 1259 | Bias sequence turns HV down to 40V |
| 1304 | Tower = 29.7 mK |
| 1305 | Stop/Start the MIDAS run manually after 15 min to avoid DCRC glitching. |
| 1322 | Stop/Start the MIDAS run manually after ~30 min total to avoid DCRC glitching. |
| 1336 | Notice that HV leakage is high because we're filling the LN2 dewar HV=40V, Vleak=44 mV, Vdet=22 V |
| 1337 | Stop/Start the MIDAS run manually after 45 min total to avoid DCRC glitching. |
| 1350 | Stop MIDAS run manually after 60 min total. Tower = 29.7 mK |
| 1351 | Turn bias down to 0V and flash. |
| 1405 | Start LHe transfer (MB = 31.5%) |
| 1451 | End LHe transfer (MB = 92.1%) |
| 1520 | Adjust DCRC3pC Front-end Gain up from 10 to 15. This may make it more stable. (Currently it looks stable but it has a low offset - the others are all closer to 0.) It looks like it increases the amplitude of a 350 kHz noise peak a little (x2 maybe?) but otherwise no big change. |
| 1525 | Place 22Na source inside lead shield at the bottom on the north-west side of the fridge. |
| 1529 | Start 10 x 2hr Na datasets at -80V split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-80×10-15_5PreBias-30Flash-30wait-2hrData-10minSubRun.msl CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = (10/10/10)/(10/15/10) NaI detector: 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V, Pos) / Ortec 575A(gain=10, shaping = 3us, Pos) → x10/x10 attenuator → DCRC4PB/PA, Driver Gains = 1/1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 64 (64 samples) 1000 BOR randoms, trigger on DCRC3pB/C/D threshold = 7/10/9 |
| 1550 | Adjust driver offsets on most channels to get them closer to desired baseline (around -0.9V) |
| 1630 | Fill LN2 cold trap full. |
| Around 1630 the Linux cluster stopped working, and the sequence stopped with an error (although MIDAS is still running). The error looks like the same as the one earlier today. | |
| 1740 | Dial HV down to 0V using change_HV sequence |
| 1747 | Flash DCRCs 1,3 for 30 seconds |
| 1843 | Start 10 x 2hr Na datasets at -80V split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-80×10-15_5PreBias-30Flash-30wait-2hrData-10minSubRun.msl CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = (10/10/10)/(10/15/10) NaI detector: 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V, Pos) / Ortec 575A(gain=10, shaping = 3us, Pos) → x10/x10 attenuator → DCRC4PB/PA, Driver Gains = 1/1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 64 (64 samples) 1000 BOR randoms, trigger on DCRC3pB/C/D threshold = 7/10/9 Logged temperature data is on wrong thermometer starting at 1316 on 09/15. |