2016/02/10 (Wednesday)
| Setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55/33/50 | |
| Cf activation overnight | |
| 0905 | 1K Pot pressure has fallen to 3.2 mbar. Tweak needle valve open additional 5 degrees. |
| 0900 | Tower/MC(H35)/MC sensor/Cold Plate = 31.5/27.8/42/159 mK, Still = 1.17 K / 0.080 mbar, G1/G2 = 120/110 mbar, 1K Pot = 1.49 K / 1.7 mbar, Main bath = 38.4% |
| 0905 | Tweak 1K Pot needle valve open additional 5 degrees. After 30 minutes settles to 1.7 K / 20 mbar, but falling slowly. |
| 0905 | Remove Cf source from fridge |
| 0910 | Fill LN2 cold trap Dewar. |
| 0920 | Check phonons: |
| DIB2pD | railed: relock fixed it. Had to do this twice. |
|---|---|
| DIB1pB | Showing no pulses, only pulseless traces. The QET bias was set to 127.2 uA - this seems to be too high now. Reduced QET bias to 80 uA, now strong pulses seen. |
| It is suspected that the processing is currently not working correctly because the corrected charge prepulse setting is putting the charge pulses outside of the processing window. So we'll take some test series like yesterday but with the charge prepulse setting returned to 250 as it was before Feb 4. | |
| 0940 | Start 15min test background series with standard setup at -4/+4 V with FG=5/2/5, OG=3, with 1000 initial randoms, 0 ending randoms, no flash. Trigger on DIB1 phA with threshold of 20ADC bins with 150 us pileup cut window. Charge prepulse set to 250 on all three DCRCs. |
| 0955 | Stop run. Enable high-threshold on DIB1 Qi&Qo. |
| 0957 | Start 15min test background series with standard setup at -4/+4 V with FG=5/2/5, OG=3, with 1000 initial randoms, 0 ending randoms, no flash. Trigger on DIB1 phA with threshold of 20ADC bins and DIB1 qInner&qOuter each with threshold 210 ADC bins,, with 150 us pileup cut window. |
| 1012 | Stop run. |
| 1555 | 1K Pot pressure has fallen to 7.5 mbar; tweak needle valve open additional 5 degrees. After 30 minutes it settles to 1.71 K / 20 mbar. |
| 1558 | Processing issues seem fixed. Set both phonon and charge prepulse bins to 500. Check phonon pulses: |
| DIB1pA | Railed. Adjust Driver Offset. |
|---|---|
| DIB1pC | Railed. Adjust Driver Offset. |
| DIB2pD | Railed. Adjust Driver Offset. |
| DIB3pB | Railed. Adjust Driver Offset. |
| DIB3pC | Railed. Adjust Driver Offset. |
| DIB3pD | Railed. Adjust Driver Offset. |
| 1614 | Commence LHe transfer (27.1%) |
|---|---|
| 1653 | Cease LHe transfer (90.4%). |
| 1655 | Check pulses: |
| DIB1pB | Railed. Adjust Driver Offset. Now shows only pulseless traces. Adjust QET bias to 120uA. Pulses are back. |
|---|---|
| All other channels show good pulses. |
| 1705 | Fill LN2 cold trap full. |
|---|---|
| 1722 | Release pressure from Main Bath. |
| 1745 | Place Strong 88-Y source in Be disc sourceholder. |
| 1747 | Start 14 30min Y-Be series at -4/+4V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, 30s flash and 25 minute cooldown before series. Trigger on DIB1 phA with threshold of 20ADC bins and DIB1 qInner&qOuter each with threshold 210 ADC bins, with 150 us pileup cut window. |