2015/09/21 (Monday)
| Current setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → → DCRC55/33/50. | |
| Overnight: Cf source near detector for activation. Tower temperature stable. | |
| 0910 | Fill LN cold trap Dewar |
| 0915 | Remove Cf source from fridge |
| 0920 | Tower/MC(H35)/MC sensor/Cold Plate = 30.9/25.2/39.1/158 mK, Still = 1.32 K / 0.080 mbar, G1/G2 = 205 mbar, 1K Pot = 1.71 K / 22 mbar, Main bath = 16.4% |
| Circulation pressures are a bit elevated for the last couple of days | |
| 1110 | Take control of DAQ with LabVIEW after MIDAS tests. Noticed that Qbias was set to -/+4V after MIDAS tests. Zero Qbias. |
| 1117 | Apply LabVIEW settings to all 3 DIBs. Flash 30s. |
| 1205 | Start LHe transfer at 10.7% |
| 1325 | Cease LHe transfer (91.8%). |
| 1330 | More MIDAS tests. |
| 1430 | Stop MIDAS tests. Reset LabVIEW values and flash for 30s. |
| DIB2 Qo shows very regular sinusoidal noise of ~250Hz, 5mVpp. Not big enough to worry about right now. | |
| 1455 | Examine pulses after cooldown. Set phonon thresholds: |
| A | B | C | D | |
|---|---|---|---|---|
| DIB1 | 40 | 40 | 45 | 45 |
| DIB2 | 35 | 35 | 35 | 35 |
| DIB3 | 45 | 45 | 45 | 50 |
| Set trace length of 20ms. Keep Qbias at 0V. Take 1000 randoms of long-trace data. Very slow rate (~1.2Hz). Not unexpected. | |
| 1518 | Stop data. Set all QET biases to 0uA to take long trace data at superconducting state. Change Driver Offsets temporarily to unrail channels. |
| 1530 | Start 1000 randoms of long-trace superconducting data. |
| 1547 | Stop data. Set QET biases to 400uA to push TESs normal. |
| 1602 | Start 1000 randoms of long-trace normal data. |
| 1626 | Set QET biases back to standard values. Sinusoidal noise (~25mVpp, ~250Hz) now present on all DIB1 phonon channels. Less regular noise of similar frequency visible on DIBs 2 and 3 phonon channels. |
| 1634 | Set trace length back to 50ms. Take 1000 randoms at usual QET biases. |
| 1650 | Finish randoms. Flash before overnight run. |
| 1700 | Place Cf source under shield near fridge top for overnight Cf data. Data started, but then aborted because the sinusoidal noise was still visible and affecting the pulse quality. Decide to unpower DCRCs overnight, and repower in the morning to see if the noise is still present. |
| 1710 | Push Cf source down farther in dewar jacket, nearer detector for overnight activation. |
| Fill LN2 cold trap full. |