| 0125 | We incurred some minor problems with data acquisition. Overall though, data quality should be fine. There are, however, a few things to bear in mind when performing the analysis. |
| | Rather confusingly, 23 data files were collected yesterday. It appears as though 12 files were taken at -/+2 V and 11 files at +/-3 V. A quick look at the pulses with BatViewer should confirm this. |
| | Additionally, it appears as though there was no detector flash before data series 07121117_1754. It's likely this was the first +/-3 V data series. We've seen this before, and restarting the DAQDAQ2 vi seems to clear up whatever is causing the problem. The rest of the data is probably fine, and the fact there was no flash before this data series means it should probably not be included in the analysis. We shall reduce it anyway just in case we can do something with it. |
| | Finally, times between data series are rather erratic, ranging from 14 to 33 minutes. Restarting the DAQDAQ2 vi may clear up whatever is causing this problem. |
| | Restart all LabVIEW vis. |
| 0145 | Place Ba-133 source back in safe. Take Cf-252 source out of safe and install 3“ below top of mu-metal shield. Email to be sent to laboratory users to warn them of the source's presence. |
| | Start data acquistion with Cf-252 source 3” below top of mu-metal shield, triggering on phonon channels with 0.4 ms trigger delay and 3.2768 ms trace length. OR phonon trigger threshold 25 ADC bins for all phonon channels, and coincidence time set to 10 μs. Flash for 6 seconds, followed by cool down for 20 minutes. Then take twenty-four 5-minute data series at -/+2 V bias. Flash all LEDs for 6 seconds between data series with usual settings, and wait 20 minutes for cryostat to cool. Finish with a 20 minute flash and 2-hour cool down. |
| | Phonon pulses in test data series look good. Trigger rate lies between 13-14 Hz. |
| 0155 | Take advantage of detector flash to fill N2 cold trap full. |
| 0240 | A look at the pulses in BatViewer indicates that 07121117_1740 appears to be the last -/+2 V data series, and 07121117_1754 seems to be the first +/-3 V data series. |
| | A quick look at acquisition time for each data series in Table 1 is revealing. For some reason, the last -/+2 V data series had a short data acquisition time of 3 minutes. This was followed by a 10-minute series at +/-3 V, then a flash preceding a 13-minute +/-3 V data series. Not sure what to make of it, except that we should just use whatever data we have without imposing an event time cut. With such erratic behaviour, such a cut becomes difficult to impose in the analysis. There will be some degradation in neutralisation, but as long as the 356 keV line is visible, the data is good enough. |