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2014/05/21

0030 Took some time to figure out why trigger rate was so poor. It appears that placing the Cf-252 source too close to the detector seems to saturate the DAQ and kill the event rate. A compromise was reached, where the event rate does appear to suffer a little, but isn't too poor at around 10 Hz. Occasionally it does dip down to 6 Hz, and reaches 12 Hz at some moments. However, this should suffice.
Commence data acquisition with Cf-252 source: 4-hour flash followed by 2-hour cooldown. Sixteen data series each of length 15 minutes, taken at -/+3.5 V bias, interspersed by 6-second flash and 20-minute cooldown periods. OR trigger on phonon channels.
1040 Fill N2 cold trap full.
1820 Remove Cf-252 source. Commence data acquisition: 30-second flash followed by 30-minute cooldown. Two data series of length 5 minutes at -/+3.5 V bias, interspersed by 6-second flash and 20-minute cooldown periods. OR trigger on phonon channels. First data series: C2 unlocked. Second data series: all DIB 2 SQUIDs unlocked.
2340 Commence data acquisition with Cf-252 source: 4-hour flash followed by 2-hour cooldown. Sixteen data series each of length 15 minutes, taken at -/+3.5 V bias, interspersed by 6-second flash and 20-minute cooldown periods. OR trigger on phonon channels.
2345 Fill N2 cold trap full.