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2015/06/26 (Friday)

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0810 Remove Cf source from fridge.
0814 Flashing detector overnight. MC/Tower/Cold Plate = 87.9/214/159 mK, Still = 2 mW / 1.11 K / 0.13 mbar, G1/G2 = 230/215 mbar, 1K Pot = 1.69 K / 16 mbar, Main bath = 20.7%
0833 Stop flashing. Turn off DIB1 LEDs: Tower temperature falls from 214 to 180 mK; for DIB2 180 to 65 mK; for DIB3 65 to base
0840 Fill LN2 cold traps.
0847 Adjust driver offsets:
Current driver offsets
pA pB pC pD
DIB1 -0.018 -0.014 -0.030 -0.024
DIB2 0.032 0.044 0.032 0.028
DIB3 -0.098 -0.022 -0.108 -0.156
1301 Accidentally left crystal biased for a long time. Flash for 1 minute. Before flash, zero Q bias and temp. rises to ~41 mK, then settles back down. Weird. No discernible reason… Flash!
1350 Leak-checked LHe transfer tube vacuum jacket. The leak seen previously at the valve was not present. The leak at the joint between the fridge-side tube and the flexible section returned (maybe the vacuum grease finally got sucked through). Applied some Q-compound to this joint. Before the Q-compound the steady-state leak was 20 pbarL/s, after applying it the rate fell to 1 pbarL/s.
1400 Boards in bad state - No pulses and tower temp. ~5 mK warmer. Unplug then replug boards - Temp. decreases.
1418 Commence LHe transfer (9.8%).
1504 Finished LHe transfer (91.3%).
1510 ZAP all SQUIDS and reapply settings; Change C2 driver offset from -0.014 V to 0.038 V; Increase C1 threshold from 25 to 35 ADC bias; Change C1 driver offset from -0.006 V to -0.036 V.
1527 Take 30 min. of -4/+4 V data (background).
1605 Stop data run, zero Q bias, flash for 10 sec.
1612 Flashed for I'm not sure how long… 60 - 70 seconds, I think. Took about 16 min. to cool.
1702 Stop data run, zero Q bias, flash 10 seconds. Cool down takes 16 minutes.
1706 Fill LN2 cold trap full.
1723 Start data run.
1750 Stop data run. Zero Q. Place Cf source in shield at detector level.

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