An algorithm for Monte Carlo simulation of bremsstrahlung emission by electrons
An algorithm for Monte Carlo simulation of bremsstrahlung emission by electrons based on the framework of SuperMC is presented in this paper with efficient and accurate methods to sample the angular distribution and energy of bremsstrahlung photons. The photon energy is sampled according to scaled energy-loss differential cross sections tabulated by Seltzer and Berger. A novel hybrid model for photon angular distribution by low- and high-energy incident electrons is developed. The model uses Tsai’s full form of angular distribution function with atomic form factors for high-energy incident electrons. For electrons of <500 keV, a simple efficient and accurate analytical distribution function is developed, using adjustable parameters determined from the fitting of numerical values of the shape functions tabulated by Kissel et al. The efficiency of sampling photon energy is 80%. Our angular sampling algorithm for high-energy electron bremsstrahlung based on Tsai distribution function is very efficient (sampling efficiency ~70%) in the useful photon energy range.
KeywordsBremsstrahlung Monte Carlo SuperMC Differential cross section Angular distribution
The authors would like to show their great appreciation to other members of FDS Team for their support and contribution to this research.
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