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arXiv · 2507.15380

Radiative corrections to the parity-violating spin asymmetry

D. H. Jakubassa-Amundsen·X. Roca-Maza
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Abstract

The parity-violating spin asymmetry Apv for elastic electron scattering from spin-zero nuclei, together with its QED corrections, is evaluated non-perturbatively within the phase-shift analysis. Dispersion corrections, taking into account low-lying transient nuclear excitations, are estimated with the help of the lowest-order $\gamma Z$ box diagrams. Collision energies between 5 $-$ 500 MeV are considered, and results are provided for the $^{12}$C and $^{208}$Pb target nuclei. In addition, we have evaluated Apv at GeV energies and small scattering angles -- relevant for the Pb Radius Experiment (PREx) -- revealing that the low-lying nuclear excited states give no measurable dispersive contribution. However, they are important at lower energies and backward angles.

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D. H. Jakubassa-Amundsen, X. Roca-Maza. 2025-07-21. Radiative corrections to the parity-violating spin asymmetry. https://arxiv.org/abs/2507.15380

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