Improving the accuracy of neutrino energy reconstruction in charged-current quasielastic scattering off nuclear targets

TL;DR

This paper presents a theoretical study on neutrino energy reconstruction in quasielastic scattering, incorporating nuclear effects beyond impulse approximation, and proposes an improved energy reconstruction method validated against electron-scattering data.

Contribution

The study introduces a generalized spectral function formalism to account for nuclear effects, improving neutrino energy reconstruction accuracy over traditional models.

Findings

Electron-scattering cross sections match experimental data well.

Nuclear effects significantly impact neutrino energy reconstruction.

Proposed method reduces biases in energy estimation.

Abstract

We report the results of a theoretical study of quasielastic electron and neutrino interactions with carbon. Our approach takes into account the effects of final-state interactions between the struck nucleon and the residual nucleus, neglected in the impulse approximation, through a generalization of the spectral function formalism. The calculated electron-scattering cross sections turn out to be in very good agreement with the available data over a broad kinematical region. The impact of nuclear effects on the reconstruction of neutrino energy in charged-current quasielastic processes is also studied, and the results of our approach are compared to the predictions of the relativistic Fermi gas model, routinely employed in most Monte Carlo simulations. Finally, we discuss the limitations of the existing procedure for energy reconstruction and propose a new, improved, one. At energy ~600 MeV, we observe a sizable difference between neutrino and antineutrino scattering, important for the measurements of charge-parity symmetry violation. Our analysis suggests that a reliable determination of neutrino energy can only be obtained from models validated by a systematic comparison to the available electron-scattering data.