Charmonium in lattice QCD and the non-relativistic quark-model

TL;DR

This paper compares lattice QCD calculations of charmonium spectrum with a non-relativistic quark model, identifying hybrid states and providing a bound-state interpretation of the data.

Contribution

It introduces a method to relate lattice QCD results to non-relativistic potential models, including the identification of hybrid states via gluonic field components.

Findings

Lattice QCD results align with non-relativistic model predictions for charmonium.

Hybrid states are distinguished by their unique gluonic field overlaps.

The approach offers a new interpretation framework for bound states in QCD.

Abstract

We compare the results of a numerical lattice QCD calculation of the charmonium spectrum with the structure of a general non-relativistic potential model. To achieve this we form the non-relativistic reduction of derivative-based fermion bilinear interpolating fields used in lattice QCD calculations and compute their overlap with c-cbar meson states at rest constructed in the non-relativistic quark model, providing a bound-state model interpretation for the lattice data. Essential gluonic components in the bound-states, usually called hybrids, are identified by considering interpolating fields that involve the gluonic field-strength tensor and which have zero overlap onto simple c-cbar model states.