Baryon masses at O(a^2) in chiral perturbation theory

TL;DR

This paper derives the baryon chiral Lagrangian up to order a^2, calculates nucleon and delta masses including lattice artifacts, and compares these results across different lattice actions and symmetry violations.

Contribution

It provides the first detailed derivation of baryon masses at O(a^2) in chiral perturbation theory for various lattice actions and symmetry considerations.

Findings

Calculated baryon masses at O(a^2) including lattice artifacts.

Analyzed effects of O(4) rotational symmetry violation.

Compared results across different lattice quark actions.

Abstract

The chiral Lagrangian for the Symanzik action through O(a^2) for baryons is obtained. We consider two flavor unquenched and partially quenched lattice theories, allowing for mixed actions in the latter. As an application, we calculate masses to O(a^2) for the nucleons and deltas, and investigate the corrections due to the violation of O(4) rotational invariance. These results are contrasted with those in the meson sector for lattice simulations using mixed and unmixed actions of Wilson and Ginsparg-Wilson quarks.