Meson and Baryon dispersion relations with Brillouin fermions

TL;DR

This study compares meson and baryon dispersion relations using Brillouin and Wilson fermions on a gauge ensemble, highlighting the advantages of Brillouin fermions at higher quark masses, especially for charm quarks.

Contribution

The paper demonstrates that Brillouin fermions maintain relativistic dispersion relations at charm quark masses, outperforming Wilson fermions which exhibit significant cut-off effects.

Findings

Brillouin fermions show relativistic behavior at charm quark masses.

Wilson fermions exhibit severe cut-off effects at high quark masses.

Masses of  baryons were successfully determined.

Abstract

We study the dispersion relations of mesons and baryons built from Brillouin quarks on one N_f=2 gauge ensemble provided by QCDSF. For quark masses up to the physical strange quark mass, there is hardly any improvement over the Wilson discretization, if either action is link-smeared and tree-level clover improved. For quark masses in the range of the physical charm quark mass, the Brillouin action still shows a perfect relativistic behavior, while the Wilson action induces severe cut-off effects. As an application we determine the masses of the \Omega_c^0, \Omega_{cc}^+ and \Omega_{ccc}^{++} baryons on that ensemble.