Regge spectrum from holographic models inspired by OPE

TL;DR

This paper proposes a modification to holographic QCD models that incorporates local vacuum condensates, successfully reproducing the linear Regge trajectories for meson spectra by linking the slope to the gluon condensate.

Contribution

It introduces a simple method to include local condensates into holographic models, resolving the issue of Regge spectrum reproduction in AdS/QCD frameworks.

Findings

Regge trajectories can be obtained by incorporating local condensates.

The slope of meson trajectories is determined by the gluon condensate.

Standard models lack the dimension-2 condensate, which is crucial for accurate spectrum modeling.

Abstract

The problem of obtaining the Regge-like behaviour for meson mass spectrum in the hard-wall AdS/QCD models is addressed. We show that the problem can be solved by a simple incorporation of the effects of local vacuum condensates into such models. The slope of trajectories turns out to be determined by the local condensate of dimension~2 that is absent in the standard Operator Product Expansion. This pitfall, however, can be escaped by means of physically plausible modification of boundary conditions for the holographic fields corresponding to the usual gluon condensate, the latter then determines the slope.