Another attempt at the Single Photoelectron Peak
PMT 14 was biased at 1100V in the darkroom with a varying threshold. The new oscilloscope (LeCroy 434) was used to record the pulse information.
| Table 1: Data Runs used to find SPE |
| Run | Date | Threshold (mV) | Number of Events | Data file |
| 1 | 04/07/2014 | -1.00 | 10548 | 20140407_PMT14_SPE_1100V_1mV-threshold.dat |
| 2 | 04/07/2014 | -2.00 | 10463 | 20140407_PMT14_SPE_1100V_2mV-threshold.dat |
| 3 | 04/08/2014 | -1.00 | 25866 | 20140408_PMT14_SPE_1100V_1mV-threshold.dat |
| 4 | 04/17/2014 | -1.00 | 10488 | 20140417_PMT14_SPE_1100V_1mV-threshold.dat |
04/07/2014
At this point, the DAQ appears to be working correctly with a data rate of ~ 40 Hz.
| Figure 1: Possible single photoelectron peak with -1.00 mV threshold. (run 1) |
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| Figure 2: No single photoelectron peak visible with -2.00 mV threshold. (run 2) |
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04/08/2014
The “DAQ stopped DAQing” correctly at some point.
| Figure 3: No single photoelectron peak visible. (run 3) |
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04/17/2014
Many attempts occurred to fix the data taking rate of the DAQ.
| Figure 4: Still no single photoelectron peak visible. (run 4) |
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