Stochastics of multiple electron–photon head-on collisions

Abstract

The problem of stochastic in multiple electron–photon head-on collisions has been considered in the paper. A kinetic theory for the distributions over the electron energy and collisions number and the equations for these distribution moments are used for this study instead of frequently used approximate estimations. An iterative method has been suggested for solving the equations for the distribution moments. It has been shown that the variance of the energy distribution as a function of the mean number of collisions has a maximum at some value of n ̄ if the incident energy spread of electrons is less than some limit value. That is, the energy spread damping due to the head-on electron–photon collisions takes place for electrons with large enough variance of energy distribution. Analytical formulas and Monte Carlo simulation show that multiple scattering of electrons influences on the spectra both electrons and photons even for the photon target of small thickness. In particular, multiple scattering of electrons leads to broadening of spectra of photons with small emission angle. This fact has to be taken into account in the nuclear and high energy physics experiments where such photon beams can be used and beam monochromaticity is important.