2017/05/19 (Friday)
| Setup: DIB1/3/4 → 3.2 MHz filters 3/1/2 → cable 3/1/2 →gender changer 3/1/2 → HVConn 1/3/2 → HV 1/2 → DCRC55/DCRC33 | |
| PuBe source in paraffin barrel behind shield (west side) Na-22 source hanging along southeast column of fridge stand |
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| Took NaI-triggered data overnight @50V. Data looks good. | |
| 0905 | Tower = 33.0 mK, Main bath = 34.4% |
| 0905 | HV = 50.00 V, Vtest = 2.40 mV → Vdetector = 49.0 V |
| Monitored Vtest overnight with webcam. It went slowly and steadily down from about 3.0 to about 2.4 mV. So Vdetector went steadily up from 48.8 to 49.0 V. | |
| 0925 | Dial HV down to 0V |
| 0925 | Fill LN2 cold trap bath |
| 0940 | Begin 60 minute bake with DCRCs 1&2 |
| 1127 | put out 22Na source for HPGe calibration |
| 1140 | Looks like the DAQ has crashed. The web pages won't connect. The bake should be over but the detector is still at 0.5 K. |
| 1145 | Restarted the DAQ. Maybe the sequence finished then, but I wasn't sure, so I reran the flash sequence with just a 10 second flash to make sure it went through the end steps. Tower is now cooling. |
| 1204 | Start LHe transfer @ main bath = 30.0% |
| 1505 | Finish IbIs on DCRC1pA/DIB1pA/Side1pE |
| 1545 | Put 22Na in safe, hang 88Y from meter stick near SW column of fridge rack |
| 1620 | Finish IbIs on DCRC1pB/DIB1pB/Side1pB |
| 1635 | Finish IbIs on DCRC1pC/DIB1pC/Side1pD |
| All three of these IbIs show that QETbias*prefactor is still close to 30 uA as originally set. | |
| 1705 | Fill LN2 cold trap bath |
| 2222 | returned 88Y source to safe |
| 2224 | turn apparent voltage up to 80V for pre-bias |
| 2232 | I guess this was a little high for pre-bias because I didn't know we were back in low leakage mode. We are at 77V true bias now |
| 2233 | set the voltage to 50V to get ready for data taking, ended up at 51.1V apparent with 2.48 mV leakage, giving 50.1V true |
| 2254 | Start 12 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/15/5)/(3/4/4), OG = 4/2, QET biases = table from Apr 28, with 1000 beginning randoms, no flashing, and a 500ADC bin threshold trigger on DCRC4 pA (external trigger). Running OR trigger of NaI detectors with PuBe source on west side of shield. NaI detector C has 311 mV threshold and detector B has 288 mV threshold |