One and Two-Body Current Contributions to Lepton-Nucleus Scattering

TL;DR

This paper enhances lepton-nucleus scattering models by incorporating interference effects between one- and two-body currents within the spectral function formalism, leading to improved agreement with experimental data.

Contribution

It introduces a method to include interference effects in the spectral function formalism for more accurate lepton-nucleus scattering predictions.

Findings

Interference effects significantly increase the transverse response functions.

Enhanced cross sections improve agreement with experimental data.

Implications for neutrino-oscillation measurements and nucleon form factors.

Abstract

Modeling lepton-nucleus scattering with the accuracy required to extract neutrino-oscillation parameters from long- and short-baseline experiments necessitates retaining most quantum-mechanical effects. One such effect is the interference between one- and two-body current operators in the transition currents, which has been known to enhance the cross-sections, especially in transverse kinematics. In this work, we incorporate such interference in the spectral function formalism, which combines relativistic currents and kinematics with an accurate description of the initial target state. Our analysis of lepton-scattering off $^{12}$C demonstrates that interference effects appreciably enhance the transverse electromagnetic response functions and the flux-folded neutrino-nucleus cross section, in both cases, improving the agreement with experimental data. We discuss the impact on the neutrino-oscillation program and the determination of nucleon axial form factors.