Electroweak nuclear response in quasi-elastic regime

TL;DR

This paper compares nuclear effects in quasi-elastic electron and neutrino scattering using recent experimental data, revealing that current models cannot simultaneously describe both with the same parameters, indicating a need for new theoretical approaches.

Contribution

It introduces a systematic comparison of electron and neutrino quasi-elastic scattering data with advanced nuclear models, highlighting limitations of existing approaches and proposing the necessity for a new paradigm.

Findings

Electron and neutrino cross sections cannot be described with the same axial mass.

Current models fail to simultaneously fit electron and neutrino data.

A new theoretical framework is needed for accurate neutrino scattering predictions.

Abstract

The availability of the double-differential charged-current neutrino cross section, measured by the MiniBooNE collaboration using a carbon target, allows for a systematic comparison of nuclear effects in quasi-elastic electron and neutrino scattering. The results of our study, based on the impulse approximation scheme and a state-of-the-art model of the nuclear spectral functions, suggest that the electron cross section and the flux averaged neutrino cross sections, corresponding to the same target and comparable kinematical conditions, cannot be described within the same theoretical approach using the value of the nucleon axial mass obtained from deuterium measurements. We analyze the assumptions underlying the treatment of electron scattering data, and argue that the description of neutrino data will require a new {\em paradigm}, suitable for application to processes in which the lepton kinematics is not fully determined.