2018/08/23 (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) → DCRCX(4) DCRC33(2) → kepco 1kV power supply → HV input |
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| status: Took SiHV+NaI PuBe data overnight. System crash last night, MIDAS is down, last series in /byseries is 07180822_1949. 40V bias on since 18:43 with no flashes since. | |
| 0950 | Tower/MC/Coldplate = 30.6/29.3/184 mK, Still = 1.4±0.1 K / 0.070 mbar, G1/G2 = 126/119 mbar, 1K Pot = 1.61 K / 22 mbar, Turbo on IVC = 1.0 nbar, MB = 34.3% |
| 0955 | Restart MIDAS DAQ and programs. Sequence is continuing where it left off in the middle of a data series. Hit Stop Immediately |
| 1000 | Fill LN2 cold trap bath |
| 1000 | Dial HV down to 0V using sequence script change_HV_40_to_0_DCRC2.msl |
| 1020 | Flash DCRC1,3 for 30 seconds |
| 1235 | 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 |
| 1540 | Realize that NaI detectors B and C were plugged into the opposite DCRC Phonon ADC channels this whole time! NaI Detector B is really connected to the Ortec 452 and DCRC4pB, while NaI detector C is connected to the Ortec 572 A and DCRC4pA. So the setup has actually been: 1.1kV → NaI B/C → Ortec 452(gain=5, shaping = 6 us, output=10V) / Ortec 575A(gain=10, shaping = 3us) → DCRCX(4)pB/A Update: This has now been corrected in all previous run diary entries. |
| 1548 | Start test data series inputting fake exponential pulses into the NaI amplifiers. Use Agilent 33521A to input exponential pulses into both Ortec amplifiers (setup as above) at 1 kHz rate with rise/fall time = ~20 ns and ~400ns ns, kinda similar to the pulse shapes output by the NaI detectors. Vary amplitude approximately every minute using the following values (50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200) mVpp. Trigger on DCRC4pA/B = 2/2 \\This didn't get above the position of the 511 keV line. Need to go bigger. |
| 1613 | Begin LHe transfer @ MB = 24.0% |
| 1644 | Start test data series inputting fake exponential pulses into the NaI amplifiers. Use Agilent 33521A to input exponential pulses into both Ortec amplifiers (setup as above) at 1 kHz rate with rise/fall time = ~20 ns and ~400ns ns, kinda similar to the pulse shapes output by the NaI detectors. Vary amplitude approximately every minute from 1 Vpp to 10 Vpp in steps of 0.5 Vpp. Trigger on DCRC4pA/B = 2/2 |
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| Both amplifiers seem to saturate around 4.5Vpp input. However, this may be simply due to a shifting baseline of the function generator. The splitting of each amplitude appears to be an effect of the pulse generator as the event amplitudes follow a repeating pattern within each pulse amplitude setting. This is not yet fully understood. |
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| 1710 | Fill LN2 cold trap bath |
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| 1712 | End LHe transfer @ MB = 93.5% |
| 1741 | Start 7 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-40×7-15_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 |