The HepMC3 package is an object oriented, C++ event record for High Energy Physics Monte Carlo generators and simulation. Since the first implementation, described in M. Dobbs and J.B. Hansen (Comput. Phys. Commun. 134 (2001) 41), the package has undergone several modifications and in particular, the latest HepMC3 series is a completely new re-write using currently available C++11 techniques.

This is a new version of the HepMC library already available in Fedora. However, it is not an update that is a drop in replacement for the old version.