A universal implementation of radiative effects in neutrino event generators

Abstract

Due to the similarities between electron-nucleus ($eA$) and neutrino-nucleus scattering ($\nu A$), $eA$ data can contribute key information to improve cross-section modeling in $eA$ and hence in $\nu A$ event generators. However, to compare data and generated events, either the data must be radiatively corrected or radiative effects need to be included in the event generators. We implemented a universal radiative corrections program that can be used with all reaction mechanisms and any $eA$ event generator. Our program includes real photon radiation by the incident and scattered electrons, and virtual photon exchange and photon vacuum polarization diagrams. It uses the ``extended peaking" approximation for electron radiation and neglects charged hadron radiation. This method, validated with GENIE, can also be extended to simulate $\nu A$ radiative effects. This work facilitates data-event-generator comparisons used to improve $\nu A$ event generators for the next-generation of neutrino experiments.