The lowest-lying baryon masses in covariant SU(3)-flavor chiral perturbation theory

TL;DR

This paper uses covariant SU(3)-flavor chiral perturbation theory up to next-to-leading order to analyze baryon masses, successfully describing lattice QCD data and improving extrapolation to physical masses, with implications for hadron phenomenology.

Contribution

It demonstrates that covariant chiral perturbation theory at NLO accurately describes baryon masses and lattice data, enhancing extrapolation methods beyond leading-order approaches.

Findings

Good fit to lattice QCD data at NLO

Improved extrapolation to physical masses over linear methods

Predictions for pion-baryon and strange-baryon sigma terms

Abstract

We present an analysis of the baryon-octet and -decuplet masses using covariant SU(3)-flavor chiral perturbation theory up to next-to-leading order. Besides the description of the physical masses we address the problem of the lattice QCD extrapolation. Using the PACS-CS collaboration data we show that a good description of the lattice points can be achieved at next-to-leading order with the covariant loop amplitudes and phenomenologically determined values for the meson-baryon couplings. Moreover, the extrapolation to the physical point up to this order is found to be better than the linear one given at leading-order by the Gell-Mann-Okubo approach. The importance that a reliable combination of lattice QCD and chiral perturbation theory may have for hadron phenomenology is emphasized with the prediction of the pion-baryon and strange-baryon sigma terms.