Inclusive Electron Scattering And The GENIE Neutrino Event Generator

TL;DR

This paper enhances the GENIE neutrino event generator by incorporating electron scattering data to improve modeling of neutrino-nucleus interactions, especially in the quasielastic and meson exchange current regimes.

Contribution

The authors revised the GENIE generator to include electron scattering physics, enabling better testing and validation of neutrino interaction models using electron data.

Findings

$e$-GENIE describes QE and MEC regions well with SuSAv2 models.

The model underperforms in resonance-dominated higher energy transfer interactions.

Inclusion of bremsstrahlung effects improves the electron scattering simulation.

Abstract

The extraction of neutrino mixing parameters from accelerator-based neutrino oscillation experiments relies on proper modeling of neutrino-nucleus scattering processes using neutrino-interaction event generators. Experimental tests of these generators are difficult due to the broad range of neutrino energies produced in accelerator-based beams and the low statistics of current experiments. Here we overcome these difficulties by exploiting the similarity of neutrino and electron interactions with nuclei to test neutrino event generators using high-precision inclusive electron scattering data. To this end, we revised the electron-scattering mode of the GENIE event generator ($e$-GENIE) to include electron-nucleus bremsstrahlung radiation effects and to use, when relevant, the exact same physics models and model parameters, as the standard neutrino-scattering version. We also implemented new models for quasielastic (QE) scattering and meson exchange currents (MEC) based on the theory-inspired SuSAv2 approach. Comparing the new $e$-GENIE predictions with inclusive electron scattering data, we find an overall adequate description of the data in the QE- and MEC-dominated lower energy transfer regime, especially when using the SuSAv2 models. Higher energy transfer-interactions, which are dominated by resonance production, are still not well modeled by $e$-GENIE.