Fig. 1. Diagram of the generation principle of dark electron in SiPM

Fig. 2. Diagram of the characteristic signature of dark electrons in SiPM

Fig. 3. Block diagram of the experimental approach to SiPM dark electron spectroscopy measurement

Fig. 4. Spectra of dark electrons with different voltage values under a gain of 18 dB

Fig. 5. Block diagram of the measurement of the number of photons generated by muse in an optical fiber

Fig. 6. Temporal sequence diagram of each signal (color online)

Fig. 7. Comparative display of optical fiber emission spectrum (narrow curve) and quantum efficiency of SiPM at 4.5V overvoltage (wide curve)

Fig. 8. Spectrum of photon numbers generated by muons in a 1 mm diameter fiber

Fig. 9. Spectrum of photon numbers generated by muons in a 2 mm diameter fiber

Fig. 10. Comparison of muon data obtained through random sampling with S&D models

Fig. 11. Simulation of muon energy deposition in optical fibers