2018/08/31 (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 PuBe data overnight at -30V, -50V, -40V. |
| 1105 | Tower/MC/Coldplate = 30.3/29.3/184 mK, Still = 1.4±0.1 K / 0.070 mbar, G1/G2 = 102/102 mbar, 1K Pot = 1.60 K / 19 mbar, Turbo on IVC = 1.0 nbar, MB = 34.2% |
| 1110 | Fill LN2 cold trap bath. |
| 1205 | DCRC1pB railed around 20 minutes into the last 2-hour dataset. Adjust Driver Offset (this is at 0V, so not certain will work at bias, we'll see). |
| Last night's bias scan showed progressively improved noise (in keVee sigma) as bias increased -30V to -50V. Let's try -70V. | |
| 1207 | Start 1 x 2hr -70 V background dataset split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-70-15_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 |
| 1447 | Start LHe transfer (MB = 28.6%) |
| 1543 | End LHe transfer (MB = 95.6%) |
| 1619 | Fill LN2 cold trap full. |
| 1707 | Start 6 x 2hr background datasets, first at -80V, the rest at -70V split into 10min subruns, with CDMS and NaI detectors running and DCRC2 as HV controller. Using sequence HVscan-80_70x5-15_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 | Data taking is underway at -80V. Vbias = -80.017, Vtest = -23.11 → Vdetector = -70.8V, only 88%. Open the LN2 vent valve a little more to increase the ebox purge. |