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2015/10/18 (Sunday)

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Current setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55/33/50.
Overnight: Taking background data. Looks like at some point the DAQ computer's disk became full and DAQDAQ stopped working. Tower temp stable.
0955 Main bath = 36.3%
0956 Inserted cryostat-section of the LHe transfer tube borrowed from Terry in the Goldman lab into cryostat port. Left cap off to allow He gas to purge the tube, then capped it. Tube is not as long as our old one, does not touch the funnel inside of the cryostat.
1015 Started inserting borrowed LHe transfer tube into LHe dewar.
1018 A data series began after clearing the vuk-01 disk, continuing during transfer. We stopped it early.
1020 After lowering tube into LHe dewar as low as we can go, there's still not much gas coming out of the other end of the tube. Pressurize the dewar w/ He gas.

Images of transfer setup using Goldman's transfer tube.

1023 Commence LHe transfer (35.3%).
1122 Remove hose pressurizing LHe dewar in preparation for ending transfer.
1125 Cease LHe transfer (92.6%)
To remove the transfer tube we pulled it up from the Dewar a few feet, then disconnected the two pieces at the top of the cryostat, then capped the cryostat piece and pulled the Dewar piece completely out of the Dewar. We did it as a two-person job, not clear how one would do this by oneself, but it's probably manageable (moreso than with the old tube).
1132 Fill LN2 cold trap full.
Check out phonon channels. All look good. Now that we've cleared off the old runs from the disk, we can take data.
1138 Start background data series 26 cycles at -/+2V, FG=5/2/5, OG=3, with 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after. Phonon thresholds the same as Monday's values.
There's some serious low frequency noise, but we'll power through. We've got hearty spirits.

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