2018/08/30 (Thursday)
| 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 PuBe data overnight at -40V. Vbias has varied between about -39.97 and -40.01 V, Vtest between -4.7 and -6.8 mV, so Vdetector ranges from -37.3 to -38.1 V (around 2%) |
| 0940 | Tower/MC/Coldplate = 30.2/29.1/184 mK, Still = 1.4±0.1 K / 0.065 mbar, G1/G2 = 112/101 mbar, 1K Pot = 1.61 K / 20 mbar, Turbo on IVC = 1.0 nbar, MB = 71.6% |
| 0945 | Fill LN2 cold trap bath. |
| 1011 | Reduce trigger thresholds, DCRC3pC/D 7/9 → 6/8. This will take effect on series 07180830_1010. initial look suggests these thresholds are a bit too low. Dump sizes are actually smaller, which is weird - maybe a data-choke issue. BatViewer shows a lot of “walking peaks” i.e. several triggers within one trace window, so trigger rate on the order of 1kHz - that's surely too high. |
| 1243 | Start 1 x 2hr -40 V PuBe datasets each split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-40×1-15_5PreBias-30Flash 30wait-2hrData-10minSubRun.msl CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = 10 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/D threshold = 7/9 |
| 1720 | Start 7 x 2hr PuBe datasets at -30V, then -50V, then the rest at -40V each split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-30_50_40x5-15_5PreBias-30Flash-30wait-2hrData-10minSubRun.msl CDMS detector: Driver Gains = 2x, QET biases = (280/260/305)/(140/280/295) uA, Front-End Gains = 10 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/D threshold = 7/9 |
| 1725 | Fill LN2 cold trap bath |