Heavy-quarkonium potential with input from lattice gauge theory

TL;DR

This paper develops a potential model for heavy quarkonium using nonperturbative gluon propagators from lattice gauge theory, providing a more accurate description of quarkonium spectra compared to traditional models.

Contribution

It introduces a novel approach by incorporating lattice-derived gluon propagators into potential models for heavy quarkonium, enhancing the understanding of nonperturbative effects.

Findings

Lattice-based potentials yield quarkonium spectra closer to experimental data.

The approach improves upon the Coulomb plus linear potential in describing heavy quarkonia.

Numerical results show better agreement with observed masses of bottomonium and charmonium states.

Abstract

In this dissertation we study potential models incorporating a nonperturbative propagator obtained from lattice simulations of a pure gauge theory. Initially we review general aspects of gauge theories, the principles of the lattice formulation of quantum chromodynamics (QCD) and some properties of heavy quarkonia, i.e. bound states of a heavy quark and its antiquark. As an illustration of Monte Carlo simulations of lattice models, we present applications in the case of the harmonic oscillator and SU(2) gauge theory. We then study the effect of using a gluon propagator from lattice simulations of pure SU(2) theory as an input in a potential model for the description of quarkonium, in the case of bottomonium and charmonium. We use, in both cases, a numerical approach to evaluate masses of quarkonium states. The resulting spectra are compared to calculations using the Coulomb plus linear (or Cornell) potential.