Parity violation in quasielastic electron-nucleus scattering within the relativistic impulse approximation

TL;DR

This paper investigates parity violation in quasielastic electron-nucleus scattering using relativistic models, highlighting the PVQE asymmetry's potential to probe the axial-vector sector of the weak neutral current.

Contribution

It provides a detailed analysis of the PVQE asymmetry's sensitivity to reaction mechanisms and weak form factors within a relativistic framework, emphasizing its use in studying the axial-vector sector.

Findings

PVQE asymmetry is sensitive to final-state interactions and off-shell effects.

Backward scattering measurements can improve understanding of radiative corrections.

Scaling properties of interference responses are analyzed.

Abstract

We study parity violation in quasielastic (QE) electron-nucleus scattering using the relativistic impulse approximation. Different fully relativistic approaches have been considered to estimate the effects associated with the final-state interactions. We have computed the parity-violating quasielastic (PVQE) asymmetry and have analyzed its sensitivity to the different ingredients that enter in the description of the reaction mechanism: final-state interactions, nucleon off-shellness effects, current gauge ambiguities. Particular attention has been paid to the description of the weak neutral current form factors. The PVQE asymmetry is proven to be an excellent observable when the goal is to get precise information on the axial-vector sector of the weak neutral current. Specifically, from measurements of the asymmetry at backward scattering angles good knowledge of the radiative corrections entering in the isovector axial-vector sector can be gained. Finally, scaling properties shown by the interference $\gamma-Z$ nuclear responses are also analyzed.