2017/05/18 (Thursday)
| 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 |
|
| Took NaI-triggered data overnight @~50V, last sequence began at 07:58, looks OK. | |
| 0935 | Tower = 32.9 mK, Main bath = 68.8% |
| 0935 | HV = 62.20 V, Vtest = 5.44 mV → Vdetector = 60.0 V(!) Apparently leakage decreased significantly overnight. This is from the 8600A non-portable multimeter. There's a BNC cable that splits to two clamp probes and we have pins in the clamps stuck in the two test holes. Reseating these pins caused the Vtest reading to increase to something like 40 mV but then over several minutes it relaxed back down to <6 mV. |
| 0945 | Start 1 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/15/10)/(3/4/4), OG = 4/2, QET biases = table from Apr 28, with 1000 beginning randoms, no flashing, and a 20ADC bin threshold trigger on DCRC1 pA (internal trigger on Side1 pE). 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 |
| 1120 | Fill LN2 cold trap bath |
| 1125 | Dial down HV in steps and measure Vtest, waiting 10 minutes at each step before recording Vtest. |
| HV [V] | Vtest [mV] | Ileak [nA] | Vloss [V ] | Vdetector [V] | Rtot [GOhm] | Rleak [GOhm] | Gleak [nS] |
|---|---|---|---|---|---|---|---|
| 62.2 | 4.62 | 4.62 | 1.85 | 60.35 | 13.45 | 13.05 | 0.077 |
| 60 | 4.3 | 4.3 | 1.73 | 58.27 | 13.94 | 13.54 | 0.074 |
| 50 | 3.07 | 3.07 | 1.23 | 48.77 | 16.27 | 15.87 | 0.063 |
| 40.01 | 1.97 | 1.97 | 0.79 | 39.22 | 20.29 | 19.89 | 0.05 |
| 30 | 1.12 | 1.12 | 0.45 | 29.55 | 26.76 | 26.36 | 0.038 |
| 20 | 0.44 | 0.44 | 0.18 | 19.82 | 45.41 | 45.01 | 0.022 |
| 10 | 0.03 | 0.03 | 0.01 | 9.99 | 333 | 332.6 | 0.003 |
At HV=50V the leakage is similar to what it had been last weak. The leakage in nS is not constant but rather proportional to HV above 20V, with a dropoff below 20V. Not sure what that means, but it clearly isn't ohmic.
| 1230 | Dial HV down to 0V |
|---|---|
| 1240 | Start 60 minute bake with DCRCs 1&2 |
| 1522 | Take IbIs test data series. The sequence starts with ODBSET “/Logger/Write as CDMS series” n so it won't be copied to /rawdata with standard naming conventions. It should stay in /livedata as MIDAS runs 6573 and 6574. For processing purposes I created a dummy directory in /rawdata, 07170518_2500 (today's data but with a fictional time of day) and copied the two MIDAS series into it and renamed them with the standard dump naming conventions. (I did this as sudo cdmsssoft which seems to have given the directories and files the correct group and permissions.) |
| 1556 | Dial HV up to 65 V. After 10 minutes dial HV down to 50.00 V. |
| 1630 | DCRC1pC pulses are “hairy” (much larger high-frequency noise near the peak of a pulse). It looks like it only affects TES-saturated pulses. Adjusting front-end gain doesn't help much. |
| 1630 | HV = 50.00 V, Vtest (Fluke 8600a) = 3.11 mV → Vdetector = 48.8 V. |
| 1633 | Start 16 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 |
| 1655 | Fill LN2 cold trap bath |