2017/06/08 (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(1)/DCRC33(2) | |
| PuBe source in paraffin barrel behind shield (west side) | |
| 0013 | came in and noticed it's a little warmer in the lab, Vtest is at 13.47 mV, making Vdetector = 46.07V |
| 0013 | the channels still look OK and unrailed |
| 0014 | sequence stopped, turn voltage down |
| 0014 | retrolog (Anthony) 900s bake |
was there a bake here?? from the temperature record and from the settings on the flash tool looks like a 15 minute bake was done starting at 00:21
| 0052 | pre-bias to HV = 68.8, let settle |
|---|---|
| 0106 | dial down to target voltage, looks like leakage will be around 13 mV, so target HV=55.2 |
| 0119 | HV = 55.42, Vtest = 13.6 mV → Vdetector = 49.97 V |
| 0121 | Start 7 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 = 30 column from table from May 24, 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 |
| 0125 | Vtest drifted to 13.33 mV before I left → Vdetector = 50.08 V |
| 0745 | Tower = 33.2 mK, Main bath = 39.6% |
| 0745 | HV = 55.42 V, Vtest = 19.42 mV → Vdetector = 47.62 V |
| currently about halfway through the final series in the sequence. | |
| 0748 | Stop data. Will do some tests to see if IbIs has shifted, then do bake. |
| 0800 | Measure the s/c falloff QET biases of all 6 channels, to the nearest 0.1 uA, and compare to the May 24 table. In order the difference in the falloff current between now and the standard is -0.25/-0.55/-0.35/-0.65/-0.60/-0.25. So on average they are about 0.4 uA smaller, indicating elevated parasitic power relative to 0V standard. Today's parasitic powers are slightly smaller than what I got two days ago, which was also at 50V but shortly after biasing - this is hours after biasing. |
| 0805 | Dial HV down to 0V and short leads |
| 0810 | Begin 30 minute bake using DCRCs 1&2. Actually, bake wound up being 50 minutes due to an error, see below. |
| 0815 | Fill LN2 cold trap bath |
| 0855 | Something screwy is happening with the bake - sequencer window says 900 seconds have elapsed, that's only 15 minutes. But I started it 35 minutes ago. Right now it seems to be progressing normally, but I guess it was stuck for a while? Maybe the clock restarted when I looked at the tab and woke it up? |
| uh oh - I didn't have “flash duration” set properly, it was at 0.4 hours, so it logically should have done zero loops - looks like it may be in an infinite loop. Will stop immediately then try to restore things. | |
| 0900 | did Stop Immediately, tower stayed hot. Then did a second flash of only 5 second duration, now tower is cooling. Hopefully everything got reset where it should. |
| 0910 | Check Tc on DCRC1pA/Side1pE as tower cools. Set QET bias to 0 then apply test signal to QET, 12 mVpp 100 Hz, set to trigger on test signal. Pulses appear at 72.0 mK then TES falls into s/c at about 71.0 mK. (output was 0.0085 Vpp normal, 0.0235 Vpp s/c). This Tc is somewhat higher than that measured in January. There may be a bit of systematic error - as the detector cools after a bake, heat is flowing out from the detector to the tower, so the tower thermometer may underestimate the detector temperature. So maybe it's even lower than the January measurement, using the DC method. |
| 0930 | Dial HV up to 68 V. Vtest settles at 22.2 mV → Vdet = 59.1 V, leakage is high still. |
| 0940 | Dial HV down to 57.4 V targeting Vdet = 50 V. Will iterate. |
| 0955 | HV = 56.45 V, Vtest = 15.67 mV → Vdetector = 50.16 V |
| 0958 | Start 2 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, 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 |
| 1000 | Tower = 33.5 mK |
| 1135 | Tower = 33.2 mK HV = 56.45 V, Vtest = 13.96 mV → Vdetector = 50.8 V. So leakage crept down, and Vdetector crept up during data sequence. |
| 1137 | Stop data sequence. Dial HV down to 0V and short leads. |
| 1145 | Begin 30 minute bake with DCRCs 1&2 |
| 1200 | Start LHe transfer (MB = 33.7%) |
| 1245 | Tried to measure DCRC1pB Tc using same method as for DCRC1pA earlier today, but strangely it never seemed to come out of normal, even down to 36 mK |
| 1245 | Dial HV up to 70 V |
| 1300 | HV = 70.0 V, Vtest = 18.70 mV → Vdetector = 62.5 V for the prebias. Now dial down, targeting Vdetector = 50 V |
| 1309 | Start 5 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, 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 |
| 1310 | HV = 55.30 V, Vtest = 13.29 mV → Vdetector = 49.89 V |
| 1310 | Tower = 33.1 mK |
| 1314 | End LHe transfer (MB = 91.4%) |
| 1320 | HV = 55.43 V, Vtest = 13.31 mV → Vdetector = 50.09 V |
| 1400 | HV = 55.33 V, Vtest = 14.03 mV → Vdetector = 49.70 V |
| 1430 | HV = 55.67 V, Vtest = 14.26 mV → Vdetector = 49.95 V |
| 1500 | HV = 55.73 V, Vtest = 14.35 mV → Vdetector = 49.97 V |
| 1530 | HV = 55.76 V, Vtest = 14.16 mV → Vdetector = 50.08 V |
| 1620 | HV = 55.68 V, Vtest = 14.0 mV → Vdetector = 50.06 V |
| 1625 | Fill LN2 cold trap bath |
| 1645 | Put Na-22 source near SE column of fridge |
| 1650 | HV = 55.61 V, Vtest = 13.74 mV → Vdetector = 50.09 V |
| 1812 | sequence is finished, turn down HV |
| 1819 | do a 900s bake |
| 1849 | turn up voltage to HV = 69V, for pre-bias, wait to settle |
| 1911 | return 22Na source to safe |
| 1924 | HV = 55.5 V, Vtest = 13.76 mV → Vdetector = 49.990 V |
| 1925 | Start 5 1-hour data series of 1-sided 50V HV coincidence data with Frontend Gain = (15/10/10)/(4/4/4), OG = 4/2, QET biases = 30 column from table from May 24, 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 |
| 1935 | tower temp is 33.3 mK |
| 1935 | Vtest has drifted to 13.66 mV |