| | Setup: DIB1/3/4 → SL 27/19/20 → 3.2 MHz filters → cables 2,1,3 → HV board inputs 1,3,2 → HV board outputs 1,2 → DCRC55(1)/50(3). DCRC4 → HV power supply. |
| 0715 | HV = 69.91 V, V_leak = 2.41 mV |
| 0715 | Tower = 21.5 mK |
| 0720 | Dial HV from 70 V down to 0 V using changeHV_70_0.msl |
| 0730 | Flash detector for 30 seconds with DCRC1,3 LEDs |
| 0835 | Tower = 21.6 mK |
| 0912 | MIDAS is down. Only dcrc_driver.exe is running. Restart MIDAS. |
| 0914 | Tower/MC/Coldplate = 21.4/25.3/148 mK, Still = 1.4 K / 0.100 mbar, G1/G2 = 241/240 mbar, 1K Pot = 1.62 K / 26 mbar, MB = 29.2% |
| 0919 | Fill LN2 cold trap full. |
| 0930 | Dial HV up to 70 V with 15% 5-minute prebias, using changeHV_0_70_preBias15_5.msl |
| 0955 | HV = 69.93 V, V_leak = 2.63 mV |
| | We'll try some more low-threshold data. Also will look over time to see if resolution in the lines starts to degrade. This time try DCRC3pC, start at threshold = 10 |
| 1001 | Start sequence of 2 60-minute background data series at HV = 70V, Driver Gains = 2x, QET biases = 480/360/440/480/380/490 uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC3pC threshold 10. |
| 1010 | Increase trigger threshold from 10 to 12. Looks like it's triggering too much. |
| 1201 | Stopped sequence for LHe transfer. |
| 1206 | Start LHe transfer (MB = 24.6%) |
| 1255 | End LHe transfer (MB = 92.4%) |
| 1301 | Start sequence of 1 60-minute background data series at HV = 70V, Driver Gains = 2x, QET biases = 480/360/440/480/380/490 uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC3pC threshold 12. |
| 1430 | Estimate event rate from random traces. Set PhononWaveformLength on DCRC1 to 131072 which is 52.4288 ms and counted visible pulses in 60 pA traces. Counted 114 pulses in 3.1457 seconds, so event rate is around 36.2 ± 3.4 Hz. |
| 1438 | Remove Na22 source from safe and place near NaI detectors. |
| 1609 | Return Na22 source to safe. |
| 1650 | Dial HV from 70 V down to 0 V using changeHV_70_0.msl |
| 1700 | Fill LN2 cold trap full. |
| 1718 | Flash detector for 30 s |
| 1736 | Connect NaI detector B signal to DCRC4PA ADC line. Using Ortec 452 shaping amplifier at 100 gain, 6us shaping time. Reduce DCRC4 phonon trace length to 0.8192 ms. |
| 1736 | Tower = 24 mK |
| 1738 | Start 83-minute background data series at HV=0 V, Driver Gains = 2x, QET biases = 480/360/440/480/380/490 uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC4pA threshold 100 with NaI detector B connected to DCRC4PA. |
| 1901 | Stop data taking |
| 1940 | Adjust Driver offsets for most channels. |
| 1947 | Start sequence of HV scan 60-minute background data series by running sequence HVscan-0_30_65_70_75V-15_5PreBias-30Flash-30wait-1hrData.msl HV = 0, 30, 65, 70, 75 V, Driver Gains = 2x, QET biases = 480/360/440/480/380/490 uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC3pD(Side1 PF) threshold 14. |
| 2051 | During first cooldown, notice that HV = 1.06 V even though DCRC4 settings should have the power supply turned off. Could the NaI signal on DCRC4PA be affecting the HV operation? |
| 2135 | Sequence says it's taking 30V data, and DCRC4 ODB settings correspond to 30V setting, but HV = 1.37 V. Something screwy is going on. Stop the sequence |
| 2139 | Changing DCRC4QI from 30V setting to 0V setting changes HV from 1.37 V to 0.16 V |
| 2148 | Changing DCRC4QO to power off HV power supply gives HV = 1.12 V |
| 2156 | Restart MIDAS programs, still have HV = 1.12 V |
| 2157 | Stop programs, telnet to DCRC4 and use 'RESET' command. HV = 0.15 V. |
| 1000 | Start dcrcdriver, HV = 1.08 V. Stop dcrcdriver, no change. Start dcrcdriver, return DCRC4 phonon trace length to 3.2768 ms, no change. Stop dcrcdriver, no change. |
| 1030 | 'RESET' DCRC4, HV = 0.15 V. Restart dcrcdriver with phonon trace length restored to 3.2768 ms, HV = 1.06 V again. |
| 1045 | Something seems to have changed since connecting the NaI signal to the phonon ADC line. Will have to see if the correct behavior returns when we disconnect it. |