Octet baryon masses and sigma terms in covariant baryon chiral perturbation theory

TL;DR

This paper analyzes octet baryon masses using covariant baryon chiral perturbation theory up to high order, incorporating finite-volume and lattice spacing effects, and determines nucleon sigma terms from lattice QCD data.

Contribution

It provides a detailed analysis of octet baryon masses with higher-order chiral perturbation theory, including virtual decuplet effects and lattice corrections, and accurately computes nucleon sigma terms.

Findings

Successful description of lattice QCD data for baryon masses.

Precise determination of nucleon sigma terms: σ_{πN}=55(1)(4) MeV, σ_{sN}=27(27)(4) MeV.

Inclusion of finite-volume and lattice spacing effects improves model accuracy.

Abstract

We report an analysis of the octet baryon masses using the covariant baryon chiral perturbation theory up to next-to-next-to-next-to-leading order with and without the virtual decuplet contributions. Particular attention is paid to the finite-volume corrections and the finite lattice spacing effects on the baryon masses. A reasonable description of all the publicly available $n_f=2+1$ lattice QCD data is achieved.Utilyzing the Feynman-Hellmann theorem, we determine the nucleon sigma terms as $\sigma_{\pi N}=55(1)(4)$ MeV and $\sigma_{sN}=27(27)(4)$ MeV.