HERACLES: An event generator for ep interactions at HERA energies including radiative processes

A Monte Carlo event generator simulating neutral and charged current ep interactions at HERA energies and beyond is described. The present version 4.0 of the generator optionally treats the ep scattering either by means of structure-function parametrizations or on the basis of parton distribution functions in the framework of the quark-parton model. Single-photon emission from the lepton line as well as self-energy corrections and the complete set of one-loop weak corrections can be included. These corrections are sufficient to describe the cross-section with an accuracy of a few percent or, if Q2≤2x103 GeV2, of less than 1%. (orig.)