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arXiv · 2505.05941

Calculation of the axial-vector coupling constant $g_A$ to two loops in covariant chiral perturbation theory

Véronique Bernard·Jambul Gegelia·Shayan Ghosh·Ulf-G. Meißner
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Abstract

We present a calculation of the leading two-loop corrections to the axial-vector coupling constant $g_A$ in two covariant versions of two-flavor baryon chiral perturbation theory. Taking the low-energy constants from a combined analysis of elastic and inelastic pion-nucleon scattering, we find that these corrections are rather moderate.

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Véronique Bernard, Jambul Gegelia, Shayan Ghosh, Ulf-G. Meißner. 2025-05-09. Calculation of the axial-vector coupling constant $g_A$ to two loops in covariant chiral perturbation theory. https://doi.org/10.1016/j.physletb.2025.139637

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