Photon-photon and photon-hadron processes in Pythia 8

Abstract

We present a new implementation of photoproduction processes in e+e- and ep collisions into Pythia 8 Monte-Carlo event-generator. In particular we discuss how the parton showers and multiparton interactions are generated with a resolved photon beam and what is the relative contribution from direct processes in different kinematical regions. As an application we show comparisons to data for charged-particle production in e+e- and ep collisions at LEP and HERA. We consider also photoproduction of dijets comparing to data for ep collisions at HERA and discuss about possibility to further constrain nuclear PDFs with ultra-peripheral heavy-ion collisions at the LHC.

Comments: Contribution to PHOTON 2017 conference, May 22 - 26, 2017, CERN, Switzerland