2021/07/15 (Thursday)
- Lab in-personnel:Pramod and Matt and Derek
| Status | Run 74 in progress. First cooldown after IVC rebuild. |
|---|---|
| Tower thermometer is reading high, probably this is a thermometer problem and the actual temperature is much lower. High noise in some of the charge channels. | |
| Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/Source_mover_board+HV_diverter_board → DCRC50(3)/55(1). Kepco 40V supplye → HV BNC. No lead/poly shield. Currently DCRC55(1) is disconnected and off, Cable 3 plugged into source mover board only. | |
| 1058 | Tower/MC/Coldplate = 196/38.7/171 mK, Still = 1.09 K / 0.08 mbar / 0 mW, G1/G2= 299/272.5 mbar, 1K Pot = 1.63 K / 20±1 mbar. MB = 29.7% |
| 1104 | Fill LN2 cold trap bath. |
| 1115 | Flash detector for 60 seconds |
| 1302 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 17/2.05/2.1/21 e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 1004/88/490/1138 e-6 |
| These are littler higher but some close to yesterday. | |
| We'll try to move the source during the data, see what happens. | |
| 1420 | Start series and start to ramp up bias but then realize that triggers aren't on - abort series, ramp down bias. |
| 1425 | Flash detector for 60 seconds |
| 1517 | Start series but something wrong with bias connections maybe? Triggering problems too. Abort series, ramp down bias. |
| 1541 | Begin LHe transfer @ MB = 21.9% |
| 1621 | End LHe transfer @ MB = 88.2% |
| 1640 | Start 45 min series of 0V/-15V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 110/70/40/120 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| 1654 | Do mvNwait +4steps×8 times, 35 second wait, with dwell = 40 and power = 6.8 V. (Around 6.78 mm/hour) This sequence will take 4min40sec and will move the source a total distance of 0.53 mm. Tower peaks around 0.9 K after first move, pulses disappear and noise rises temporarily but then pulses reappear. After 5/8 moves Tower = 1.55 K. Still seeing pulses. Max temperature 1.8 K at 16:59, then starts to cool. |
| 1700 | Around this time we tried switching off triggering and switching it back on. We're getting some overtriggering on glitches and stuff - still seeing pulses but a lot of junk triggers. |
| 1705 | Tower = 0.6 K, on its way down to base of 0.2 K |
| It may make more sense next time to do 1 move of 32 steps rather than a mvNwait sequence | |
| 1730 | Flash detector for 60 seconds |
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| It doesn't look like moving the source had any effect on the impact ionization pattern |
20210715_log.xlsx