The eta decay constant in `resummed' chiral perturbation theory

TL;DR

This paper applies resummed chiral perturbation theory to estimate the eta decay constant, comparing results with standard predictions and phenomenological data to improve understanding of pseudoscalar meson decays.

Contribution

It introduces a novel application of resummed ChPT to better estimate the eta decay constant using multiple theoretical approaches.

Findings

Resummed ChPT provides a different estimate of the eta decay constant.

Comparison shows consistency and differences with standard ChPT predictions.

The approach offers insights beyond next-to-leading order in ChPT.

Abstract

The recently developed 'Resummed' ChPT is illustrated on the case of pseudoscalar meson decay constants. We try to get an estimate of the eta decay constant, which is not well known from experiments, while using several ways including the Generalized ChPT Lagrangian to gather information beyond Standard next-to-leading order. We compare the results to published ChPT predictions, our own Standard ChPT calculations and available phenomenological estimates.