Quarkonia and heavy-light mesons in a covariant quark model

TL;DR

This paper extends a covariant quark model to include more general confining interactions and short-range forces, successfully fitting meson spectra including quarkonia and heavy-light mesons.

Contribution

It introduces a generalized confining interaction with vector and pseudoscalar components and incorporates a one-gluon-exchange kernel into the covariant quark model.

Findings

Good agreement with experimental meson spectra

Successful fit for both quarkonia and heavy-light states

Enhanced model with more general interaction structures

Abstract

Preliminary calculations using the Covariant Spectator Theory (CST) employed a scalar linear confining interaction and an additional constant vector potential to compute the mesonic mass spectra. In this work we generalize the confining interaction to include more general structures, in particular a vector and also a pseudoscalar part, as suggested by a recent study. A one-gluon-exchange kernel is also implemented to describe the short-range part of the interaction. We solve the simplest CST approximation to the complete Bethe-Salpeter equation, the one-channel spectator equation, using a numerical technique that eliminates all singularities from the kernel. The parameters of the model are determined through a fit to the experimental pseudoscalar meson spectra, with a good agreement for both quarkonia and heavy-light states.