Electron-neutrino scattering off nuclei from two different theoretical perspectives

TL;DR

This paper compares two theoretical models for electron-neutrino scattering on Carbon, analyzing their agreement and differences, and validates the models against experimental data, highlighting the importance of multinucleon contributions.

Contribution

It provides a comparative analysis of CRPA and RPA-based approaches for neutrino-nucleus interactions, including validation against T2K experimental data.

Findings

Good agreement between models at high energies

Giant resonances appear only in CRPA at low energies

Multinucleon emission is essential to match experimental data

Abstract

We analyze charged-current electron-neutrino cross sections on Carbon. We consider two different theoretical approaches, on one hand the Continuum Random Phase Approximation (CRPA) which allows a description of giant resonances and quasielastic excitations, on the other hand the RPA-based calculations which are able to describe multinucleon emission and coherent and incoherent pion production as well as quasielastic excitations. We compare the two approaches in the genuine quasielastic channel, and find a satisfactory agreement between them at large energies while at low energies the collective giant resonances show up only in the CRPA approach. We also compare electron-neutrino cross sections with the corresponding muon-neutrino ones in order to investigate the impact of the different charged-lepton masses. Finally, restricting to the RPA-based approach we compare the sum of quasielastic, multinucleon emission, coherent and incoherent one-pion production cross sections (folded with the electron-neutrino T2K flux) with the charged-current inclusive electron-neutrino differential cross sections on Carbon measured by T2K. We find a good agreement with the data. The multinucleon component is needed in order to reproduce the T2K electron-neutrino inclusive cross sections.