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2015/10/26 (Monday)

	Current setup: iZIP mode, DIB1/2/3 → cables → 3.2 MHz filters → DCRC55/33/50.
	tower temperature normal
0920	DAQ stopped, LabVIEW error message on screen: “Fatal Internal Error: “objheap.cpp” line 523. You will lose any unsaved work.” Caused LabVIEW crash. Turns out Disk I: is completely full so maybe this caused the error. Note: it took 36 series (30 min series, 1 hour cycle) to fill I:.
0930	Fill LN cold trap Dewar
1000	After opening up crashed LabVIEW programs, notice that detector has been at +/-2V since the crash. Flash for 30s to neutralize crystal.
1040	Place Ba source at back of fridge, inside top most part of shield for high-voltage Ba data.
1047	Start 1000 randoms run of Ba data at -/+8V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 2000 events/file, 30s flash and 25min cooldown after. Use Wednesday's phonon thresholds.
	MultiDAQ isn't triggering because we didn't specify a trigger file… Stop data
1051	Start 1000 randoms run of Ba data at -/+8V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 2000 events/file, 30s flash and 25min cooldown after. Use Wednesday's phonon thresholds.
	Rate drops when getting to triggered data. Try raising Ba source as high as possible. That doesn't help. Raise all thresholds by 10 ADC bins. That also doesn't help.
1059	Stop data after 1000 randoms and 500 triggered events.
1103	Flash for 30s.
	Modify MultiDAQEventBuilder VI to include a 0ms wait in the loop of the state-machine. This will hopefully help to stop the processor from getting eaten up by a constantly running loop.
1120	Hear large hissing noise from back room. It's the pressure-relief port on the exhaust line of the He4 pump. Oil has spewed from it too and is on the floor. Change exhaust port from Recovery to Exhaust, and a big release of pressure comes out. Close He recovery valve leading from He4 pump exhaust line. He meter on wall is ticking faster than normal for non-transfer times. Stops ticking after ~1minute.
1125	Still = 0.11 mbar, G1/G2 = 120/105 mbar, 1K Pot = 1.68 K / 13 mbar, Main bath = 54.3%
1130	Start 30min run of Ba data at -/+8V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after. Use original thresholds ( Wednesday's phonon thresholds.)
1130	We reconnected the He4 pump exhaust to recovery. The overpressure valve opened again, and we saw the recovery pressure was elevated to about 3 PSI. It happened a couple of times, and temperature spikes were seen (not dissimilar to temperature spikes at the beginning and end of transfers). Also interestingly 250 Hz noise was seen in the phonon traces - there have been a couple of times that we have correlated this noise to high pressure in the bath, so it's likely that at least one source of this noise is gas oscillations, probably producing microphonic noise.
1134	Stop data because the computer is bogging down again.
	Set new phonon thresholds as below. Also add a 0ms wait (as with EventBuilder) to MultiDAQBoard VI.

	A	B	C	D
DIB1	36	40	42	40
DIB2	26	24	24	30
DIB3	45	50	58	48

1135	Found Bill Voje and determined that he's having trouble with unusually high pressures on his storage Dewar and he has been releasing the pressure to the bag. He says he'll try to make the pressure surges less severe. Will check with him later to see if the problem is over.

1147	Start 30min run of Ba data at -/+8V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.
	Rate still bogged down. Check CPU usage and see that rsync is using ~30% of the CPU, which is most likely why data taking is bogging down. Stop data until rsync is finished.
1153	Flash 30s.
1210	Start 30min run of Ba data at -/+8V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.
	Rate is good, though it does oscillate between 14Hz and 7Hz.
1312	Start 30min run of Ba data at +/-8V overshooting +Qbias (side 1) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.
1315	Rate bogging down more than before. Increase all thresholds by 10ADC bins. Rate is now good. New phonon trigger thresholds below:

	A	B	C	D
DIB1	46	50	52	50
DIB2	36	34	34	40
DIB3	55	60	68	58

1412	Start 30min run of Ba data at -/+6V overshooting +Qbias (side 2) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.
1515	Commence LHe transfer (46.2%).
1605	Cease LHe transfer (91.7%).
1613	Start 30min run of Ba data at +/-6V overshooting +Qbias (side 1) to 14V before starting data, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.
1655	Place Ba source back in safe. Take Soudan Cf source out of safe and place inside shield near detector for overnight Cf run. Raw event rate without source ≈34 Hz, with source ≈80 Hz
1705	Notice that 250Hz sinusoidal noise is present on the phonon channels. Remove rubber bung from top of dewar to allow some built up pressure to release. After doing this, the 250Hz noise seems to be gone (at least not noticeable anymore). Interesting.
1850	Fill LN2 cold trap full.
1613	Start 30min run of Cf data at +/-4V, FG=5/2/5, OG=3, 1000 initial randoms, 2000 events/file, 30s flash and 25min cooldown after.