EGS (program)

The EGS (Electron Gamma Shower) computer code system is a general purpose package for the Monte Carlo simulation of the coupled transport of electrons and photons in an arbitrary geometry for particles with energies from a few keV up to several hundreds of GeV. It originated at SLAC but National Research Council of Canada and KEK have been involved in its development since the early 80s.

Development of the original EGS code ended with version EGS4. Since then two groups have re-written the code with new physics:

EGSnrc, maintained by the Ionizing Radiation Standards Group, Measurement Science and Standards, National Research Council of Canada [1]

EGS5, maintained by KEK, the Japanese particle physics research facility [2]