SiPM 2 and SiPM 4 were placed in their delrin holders on either side of the wave-length shifting fiber of scintillator 1-74-1 and placed in the darkroom. No optical coupling grease was used to hold the fiber. Each event was self-triggered when both SiPM were above the trigger threshold of 8320. When a Y-88 source was present, it was placed 46 cm away from the scintillator. Both runs have a trigger parameter value of 3.
Note: background run must be rerun to access rootfile.
| Table 1: Data runs used. |
| Run | Source | Number of events | Data file |
| 1 | background | 10k | 130726_sipm2+4_background_8320threshold_wlsfiber.dat |
| 2 | Y-88 | 100k | 130726_sipm2+4_background_8320threshold_wlsfiber.dat |
| Figure 1: Baseline standard deviation for each SiPM for Y-88 run. |
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| Figure 2: Area under the pulse of the background for SiPM 2 only, SiPM 4 only, and SiPM 2 and SiPM 4 combined. |
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| Figure 3: Area under the pulse for Y-88 for SiPM 2 only, SiPM 4 only, and SiPM 2 and SiPM 4 combined. |
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The histograms of Figures 2 and 3 exclude pulses with a baseline standard deviation greater than 7 or with secondary pulses present.
| Figure 4: Comparison of the spectra of Y-88 and background. |
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The Y-88 spectrum has been scaled by a factor of 1/10 to account for the difference in the number of events.