ELMAG is a Monte Carlo program for the simulation of electromagnetic cascades initiated by high-energy photons and electrons interacting with the extragalactic background light. It was written by M. Kachelriess, S. Ostapchenko and R. Tomas.


The current version is Elmag 2.03 which can be downloaded here.


  • in version 2.03:
    • The redshift evolution for the Gilmore EBL tables was corrected. Thanks to Marco Muzio for pointing out this error.
    • One additional EBL background was contributed by Manuel Meyer.
    • A python version was contributed by Manuel Meyer.
  • in version 2.02:
    • Three additional EBL backgrounds were contributed by Andrey Saveliev.
    • The time-step dt used in the propagation of photons close to threshold was reduced: in previous versions, dt could become large relative to the evolution time of the EBL background, leading to too strong cutoffs for sources at large redshift. Thanks to Kumiko Kotera and Foteini Oikonomou for pointing out this problem.


A manual can be found here.


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