The Eta-prime Meson with Staggered Fermions

TL;DR

This study calculates the eta-prime meson mass splitting using staggered fermions on lattice configurations, confirming theoretical predictions and highlighting the role of zero modes in the mass origin.

Contribution

First lattice calculation of eta-prime mass splitting with staggered fermions comparing dynamical and quenched setups, aligning with chiral perturbation theory.

Findings

Results consistent with physical eta-prime mass

Zero modes of the Dirac operator contribute to the mass

Agreement with theoretical predictions

Abstract

We have computed the eta-prime pseudoscalar octet mass splitting using staggered fermions on both dynamical and quenched gauge configurations. We have used Wuppertal smeared operators to reduce excited state contributions. We compare our results with the theoretical forms predicted by partially quenched chiral perturbation theory in the lowest order. Using lattice volumes of size 16^3 x 32 with a^{-1}=2GeV we obtain results consistent with the physical eta-prime mass. We also demonstrate that the flavor singlet piece of the eta-prime mass comes from zero modes of the Dirac operator.