ELMAG 3.01: A three-dimensional Monte Carlo simulation of electromagnetic cascades on the extragalactic background light and in magnetic fields

Abstract

The version 3.01 of ELMAG, a Monte Carlo program for the simulation of electromagnetic cascades initiated by high-energy photons and electrons interacting with extragalactic background light (EBL), is presented. Pair production and inverse Compton scattering on EBL photons as well as synchrotron losses are implemented using weighted sampling of the cascade development. New features include, among others, the implementation of turbulent extragalactic magnetic fields and the calculation of three-dimensional electron and positron trajectories, solving the Lorentz force equation. As final result of the three-dimensional simulations, the program provides two-dimensional source images as function of the energy and the time delay of secondary cascade particles. Program summaryProgram Title:ELMAG 3.01Program Files doi:http://dx.doi.org/10.17632/gsr7dfnyx6.1Licensing provisions: CC by NC 3.0.Programming language: Fortran 90Supplementary material: See http://elmag.sourceforge.net/Nature of problem: Calculation of secondaries produced by electromagnetic cascades on the extragalactic background light (EBL), including deflections in magnetic fields.Solution method: Monte Carlo simulation of pair production and inverse Compton scattering on EBL photons; weighted sampling of the cascading secondaries; recording of energy, observation angle and time delay of secondary particles at the present epoch in a 1.5-dimensional approximation or of sky-maps in a three-dimensional approach.Restrictions: Using the three-dimensional approach, the energies of cascade photons should be above 1 GeV for Brms≲10−10 G.