2022/03/30 (Wednesday)
- Lab in-personnel: Anthony, Kitty, Matt
| Status | Run 76 in progress |
|---|---|
| Setup | Cable 2/1/3 → diverter/nothing/nothing → DCRC50(3)/DCRC55(1)/DCRCX(4) |
| 1210 | MC/Coldplate = 28.6/140 mK, Still = 1.12 K / 0.130 mbar / 0 mW, G1/G2= 181/189 mbar, 1K Pot = 18° / 1.64 K / 25±2 mbar. MB = 68.2% |
| 1210 | Goldman = 73.4 mK @ 632 uB excitation |
| 1215 | Fill LN2 cold trap bath |
| From IbIs with MC = 26.6-26.8 mK | |||
|---|---|---|---|
| DCRC channel | Detector channel | QET bias @ dP/dI = 0.7 uV | QET bias @ dP/dI = 1.0 uV |
| DCRC1pA | Side2pC | 169.2 | 172.5 |
| DCRC1pB | Side2pF | 170.05 | 175.5 |
| DCRC1pC | Side1pC | 234.8 | 255.8 |
| DCRC1pD | Side1pF | 274 | 287.1 |
| DCRC3pA | Side1pE | 246.5 | 260.8 |
| DCRC3pB | Side1pB | 225.5 | 241.7 |
| DCRC3pC | Side1pD | n/a | 258.9 |
| DCRC3pD | Side2pE | 210.5 | 216.1 |
| DCRC4pA | Side2pB | 171.7 | 178.2 |
| DCRC4pB | Side2pA | 160.8 | 170.3 |
| DCRC4pC | Side1pA | 211.8 | 229.5 |
| DCRC4pD | Side2pD | 197.5 | 209.4 |
The table above shows QET biases to achieve dP/dI of either 0.7 uV or 1.0 uV according to yesterday's IbIs measurements.
Based on the extensive mini-IbIs done in Run 75 at different temperatures, we can use the above values to estimate the true temperature of the detector (based on Goldman thermometer temperatures in Run 75). The closest fit for a temperature that makes the Run75 QET biases at dP/dI=1uV match those in the table above is Goldman = 46 mK. Obviously the Goldman thermometer is reading much higher than this now. It's a little surprising though that the predicted temperature is that high, kind of mid-range for Run 75, considering that now the MC seems to be running much colder than in R75. Also the correlation across detectors between the QET bias values in R75 vs R76 is only mediocre (should double-check that I got them mapped right).
| 1635 | Set QET biases to dP/dI=1.0uV values (second column above) and adjust driver offsets for baselines around -1 V. Adjust DCRC1pD(Side1pF) trigger threshold down to 8, looks like good pulses. |
|---|---|
| 1635 | MC = 28.6 mK |
| 1639 | Start 0V data series, 71 min long, with 1000 initial randoms, no in-run randoms, trigger on DCRC1pA threshold 8. Start series with the Start Button. |