A comparison of computational models for single electron spectra in photomultiplier tubes

An iterative method, an analytical approximation and a Monte Carlo-based model have been intercompared by calculating the probability distribution of electrons at the output of any dynodic stage of a photomultiplier tube (PMT). All three methods account for dynodes with different gains and assume a Poisson response for the PMT stages. The binomial distribution at the photocathode level was also tested using the Monte Carlo model. Single-electron spectra were computed by the three methods for a single PMT or for two PMTs working in summed-coincidence mode, and compared with experimental data obtained from a light emitting diode and a liquid scintillation spectrometer.