Regge spectra of excited mesons, harmonic confinement and QCD vacuum structure

TL;DR

This paper reviews a QCD vacuum model with Abelian gluon fields, deriving a meson effective action, and presents new systematic results for meson spectra and decay constants, linking to holographic and soft wall models.

Contribution

It introduces a novel approach to QCD vacuum modeling using Abelian self-dual gluon fields, leading to a meson effective action and systematic predictions for meson properties.

Findings

New mass spectrum predictions for radially excited mesons.

Decay constants calculated for various meson types.

Connections established between this approach and holographic QCD models.

Abstract

An approach to QCD vacuum as a medium describable in terms of statistical ensemble of almost everywhere homogeneous Abelian (anti-)self-dual gluon fields is briefly reviewed. These fields play the role of the confining medium for color charged fields as well as underline the mechanism of realization of chiral $SU_{\rm L}(N_f)\times SU_{\rm R}(N_f)$ and $U_A(1)$ symmetries. Hadronization formalism based on this ensemble leads to manifestly defined quantum effective meson action. Strong, electromagnetic and weak interactions of mesons are represented in the action in terms of nonlocal $n$-point interaction vertices given by the quark-gluon loops averaged over the background ensemble. New systematic results for the mass spectrum and decay constants of radially excited light, heavy-light mesons and heavy quarkonia are presented. Interrelation between the present approach, models based on ideas of soft wall AdS/QCD, light front holographic QCD, and the picture of harmonic confinement is outlined.