Combined theoretical analysis of the parity-violating asymmetry for ${}^{48}$Ca and ${}^{208}Pb$

TL;DR

This paper provides a comprehensive theoretical analysis of the parity-violating asymmetry in ${}^{48}$Ca and ${}^{208}$Pb, assessing uncertainties and comparing with experimental data to improve understanding of nuclear structure.

Contribution

It offers a rigorous nuclear energy density functional theory analysis of $A_{pv}$ in ${}^{48}$Ca and ${}^{208}$Pb, highlighting limitations of current models in simultaneously describing both nuclei.

Findings

Current models cannot accurately describe $A_{pv}$ in both nuclei simultaneously.

Models that fit global nuclear properties struggle to match experimental $A_{pv}$ values.

The analysis includes assessment of static electric dipole polarizability in these nuclei.

Abstract

The recent experimental determination of the parity violating asymmetry $A_{\rm pv}$ in ${}^{48}$Ca and ${}^{208}$Pb at Jefferson Lab is important for our understanding on how neutrons and protons arrange themselves inside the atomic nucleus. To better understand the impact of these measurements, we present a rigorous theoretical investigation of $A_{\rm pv}$ in ${}^{48}$Ca and ${}^{208}$Pb and assess the associated uncertainties. We complement our study by inspecting the static electric dipole polarizability in these nuclei. The analysis is carried out within nuclear energy density functional theory with quantified input. We conclude that the simultaneous accurate description of $A_{\rm pv}$ in ${}^{48}$Ca and ${}^{208}$Pb cannot be achieved by our models that accommodate a pool of global nuclear properties, such as masses and charge radii, throughout the nuclear chart, and describe -- within one standard deviation -- the experimental dipole polarizabilities $\alpha_{\rm D}$ in these nuclei.