Properties of charmonium in lattice QCD with 2+1 flavors of improved staggered sea quarks

TL;DR

This study investigates how sea quark effects influence the charmonium spectrum and leptonic decay widths using lattice QCD with 2+1 flavors of improved staggered sea quarks, providing insights into quark interactions.

Contribution

It presents a detailed lattice QCD analysis of charmonium properties with light sea quark masses as low as m_s/5, highlighting sea quark effects on mass splitting and decay widths.

Findings

Sea quark effects significantly influence mass splittings.

Leptonic decay matrix elements are affected by sea quark masses.

Results are consistent with experimental data within uncertainties.

Abstract

We use the dynamical gluon configurations provided by the MILC collaboration in a study of the charmonium spectrum and psi leptonic width. We examine sea quark effects on mass splitting and on the leptonic decay matrix element for light masses as low as m_s/5, while keeping the strange quark mass fixed and the lattice spacing nearly constant.