2016/02/17 (Wednesday)
| Setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55/33/50 | |
| Taking Y-Be data overnight, last flash ~ 6:45. | |
| 0905 | Remove Y source from fridge. |
| 0905 | Tower/MC(H35)/MC sensor/Cold Plate = 31.5/27.6/40/159 mK, Still = 1.15 K / 0.100 mbar, G1/G2 = 130/115 mbar, 1K Pot = 1.50 K / 2.0 mbar, Main bath = 70.1% |
| 0910 | Try increasing still heat to 2 mW (has been at 1 mW since yesterday morning). Still pressure increases to 0.120 mbar. Not much difference in base temperature. |
| 0915 | Fill LN2 cold trap Dewar. |
| 1055 | Check phonon pulses. None railed. |
| Prepare for Ba run: disable high-threshold charge triggers, so we're only triggering on DIB1 pA at 20ADC bins. | |
| 1101 | Start 30min Ba series at -4/+4 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown in before series. Trigger on DIB1 phA with threshold of 20ADC bins, with 150 us pileup cut window. |
| 1105 | Place Ba source inside shield behind fridge at top most part of shield. |
| 1220 | Place Ba source back in safe. |
| 1225 | Disable DCRCs 33 and 55 (DIBs 2&3), to test improvement in data taking rate. |
| 1241 | Start 10min of test background series only on DIB1 at 0/0 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with no flash before series. Trigger on DIB1 phA with threshold of 20ADC bins, with 150 us pileup cut window. |
| 1252 | Enable DCRCs 33 and 55 (DIBs 2&3), for control test of data taking rate. |
| 1255 | Start 10min of test background series on all 3 DIBs at 0/0 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with no flash before series. Trigger on DIB1 phA with threshold of 20ADC bins, with 150 us pileup cut window. |
| 1345 | Place Ba source inside shield behind fridge at top most part of shield. |
| 1349 | Start 10min of test Ba series on all 3 DIBs at 0/0 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with no flash before series. Trigger on DIB1 phA with threshold of 20ADC bins, with 150 us pileup cut window. |
| 1408 | Disable DCRCs 33 and 55 (DIBs 2&3), to test improvement in data taking rate. |
| 1410 | Start 10min of test Ba series only on DIB1 at 0/0 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with no flash before series. Trigger on DIB1 phA with threshold of 20ADC bins, with 150 us pileup cut window. |
| 1425 | Place Ba source back in safe. |
| Results of rate tests | ||||
|---|---|---|---|---|
| Background | Ba | |||
| Count | Rate | Count | Rate | |
| One DCRC | 1929 | 32 Hz | 4572 | 76 Hz |
| Three DCRCs | 1887 | 31 Hz | 4668 | 78 Hz |
| “Count” is the number of events in a single dump, | ||||
| representing 1 minute of data. | ||||
It appears that the read rate is unaffected by the raw event rate - likely it is saturated in all cases. It's possible that ~77 Hz is the maximum readout capability of a single DCRC (with six 3.2 ms traces per event).
| 1433 | Start test background series with standard setup at 0/0 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. Stop after initial randoms are done. |
|---|---|
| 1440 | On Pi-Filter Switchboard, all charge related lines already have filters switched on: 11, 27, 12, 30, 15, 31, 16, 50. In addition switch on all pB related lines to be filtered: 29, 47, 48, 33, 35, 34, 19, 18, 2. |
| Power off DCRC50, remove DSUB pi-filter connector, attach pi-filter switchboard, and repower DCRC50. Zap SQUIDs. | |
| 1520 | Check phonon traces. DIB1 pC railed. All others fine. Adjust Driver Offsets. |
| 1523 | Start test background series with charge lines and pB lines filtered at 0/0 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. Stop after initial randoms are done. |
| 1530 | Unpower DCRC50, detach pi-filter switchboard, attach DSUB pi-filter connector, and repower DCRC50. Zap SQUIDs. |
| 1540 | MIDAS FrontEnd dcrc_driver01 kept failing when attempting to zap. Checked DCRC33, and saw that it had once again been changed back to a Rev3.1 board. Changed it to a Rev3 board, and zapped just fine. |
| 1610 | After zapping, tower temperature falls, but then begins rising. All IGH pressures rising, except P2, which has fallen to 2.0mbar. 1K Pot temperature has risen to ~3.9K. The 1K Pot has run dry. G1/G2 have reached ~720mbar. P1: 800ubar. Open needle valve, 1K Pot temperature falls to 1.9K quickly, then continues falling slowly. All IGH pressures begin falling too. P2 has risen to 60mbar, then begins falling slowly to ~45. Still falling slowly. |
| Tower temperature had risen to ~60mK. Fell quickly to 58mK after adjusting 1K Pot, but now is cooling much more slowly. | |
| 1730 | Fill LN2 cold trap full. |
| 1800 | After MIDAS tests, all pulses alive except DIB1 pC. Adjust Driver Offset. All good. |
| 1805 | Place strong 88-Y source inside Be disc source holder. |
| Tower temperature at 31.35mK and stable. P2: 8.0mbar, and 1K Pot temperature: 1.665K. | |
| 1807 | Start 14 hours of 30min Y-Be series at -4/+4 V with FG=5/2/5, OG=3, with 1000 initial randoms, 1000 ending randoms, with 30s flash and 25 minute cooldown in between 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. |