2019/07/24 (Wednesday)
| 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 → DCRCX(4)/DCRC55(1) DCRC33(2) → 1kV power supply → HV input NaI B → DCRC50(3) pB Lead/poly shield erected, south wall partial lead only (with NaI detectors). |
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| PuBe source in lab behind lead stack. | |
| 0925 | Start a sequence of 8 @ 34 min series at HV = 180→327V, rate 4.31V/min, with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/495)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR, 5Hz InRun randoms, trigger on DCRC1pD threshold = 6, baseline/sample length = 120/28 (standard 16/5), phonon pre-pulse 500 (standard is 500). NaI detector: 800 V → NaI B (dynode terminated) → PS776 → Lecroy 628 Fan In/Out → Ortec 452(Neg input, G=100, shaping=6us, -10V output) → DCRC3 PB, Driver Gains = 1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 512 (512 samples) Use sequence HVdrift_8X180V_4p31VPM_loopversion_prebias_10_2_dur_34min_flashDCRC_1_4.msl |
| 0940 | Tower/MC/Coldplate = 39.1/30.2/199 mK, Still = 1.30 K/ 0.100 mbar / 0 mW, G1/G2= 113/104 mbar, 1K Pot = 1.7 K / 60±5 mbar. MB= 26.8% |
| 0943 | Fill LN2 cold trap bath. |
| 1210 | Let's do a LHe transfer between series. We'll pause the script when necessary to keep from starting new data during the transfer. |
| 1215 | Commence LHe transfer. MB = 21.6% 1K Pot pressure runs off scale for a minute, but then recovers and stabilizes. |
| 1223 | Pause Sequencer before it starts the next series. |
| 1250 | Cease LHe transfer. MB=90.6% |
| 1255 | Resume data taking Sequence. |
Some plots and info from recent PuBe data:
- Event rate = 82 Hz, calculated from randoms, threshold ~ 0.9 keV
- Write rate = 68 Hz (includes in-run randoms and noise triggers)
- Write efficiency ~ 17.5%
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Some more plots from last night's PuBe data.
- A bunch of standard quality cuts similar to those in R68
- Including Low Energy Rate cut as described in Note 55 removes trigger burst events. Using n50_200_N100<10
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| 1600 | Fill LN2 cold trap bath. |
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| 1730 | DAQ crash, probably because all the Linux machines locked up a half hour ago… looks like it stopped in the middle of the series, HV still on… |
| 1735 | Restart MIDAS and the DAQ programs (dcrc driver, tower, trigger). Sequence looks like it's starting where it left off. The series which started around 16:04 will be bad, at least the last part of it, because the bias was left constant for about an hour. |
| 2255 | Start a sequence of 8 @ 34 min series at HV = 180→327V, rate 4.31V/min, with 10% prebias for 2 minutes, flash at end with 30 min wait. CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (490/400/495)/(420/480/450) uA, Front-End Gains = (2/2/3)/(5/5/5) 1000 BOR, 5Hz InRun randoms, trigger on DCRC1pD threshold = 6, baseline/sample length = 120/28 (standard 16/5), phonon pre-pulse 500 (standard is 500). NaI detector: 800 V → NaI B (dynode terminated) → PS776 → Lecroy 628 Fan In/Out → Ortec 452(Neg input, G=100, shaping=6us, -10V output) → DCRC3 PB, Driver Gains = 1, PhononWaveFormLength = 1024 (512 samples), PhononPrepulseSamples = 512 (512 samples) Use sequence HVdrift_8X180V_4p31VPM_loopversion_prebias_10_2_dur_34min_flashDCRC_1_4.msl |
| 2235 | Stop sequence before the last series starts so we can start a new overnight sequence |