Application of Bayesian statistics to the sector of decay constants in three-flavour ChPT

TL;DR

This paper applies Bayesian statistics within resummed SU(3) chiral perturbation theory to analyze decay constants of light pseudoscalar mesons, providing constraints on low energy constants and comparing theoretical predictions with experimental and lattice data.

Contribution

It introduces a Bayesian approach to constrain low energy constants in chiral perturbation theory using decay constant data, enhancing the analysis of meson decay properties.

Findings

Constraints on L_4^r and L_5^r were obtained.

Theoretical eta decay constant predictions are consistent with experimental and lattice results.

Higher order remainders to decay constants were estimated.

Abstract

The sector of decay constants of the octet of light pseudoscalar mesons in the framework of 'resummed' $SU(3)$ chiral perturbation theory is investigated. A theoretical prediction for the decay constant of $\eta$-meson is compared to a range of available determinations. Compatibility of these determinations with the latest fits of the $SU(3)$ low energy coupling constants is discussed. Using a Bayesian statistical approach, constraints on the low energy coupling constants $L_4^r$ and $L_5^r$, as well as higher order remainders to the decay constants $F_K$ and $F_\eta$, are extracted from the most recent experimental and lattice QCD inputs for the values of the decay constants.