Generalized Soft Wall Model

TL;DR

This paper introduces a generalized soft wall holographic model for vector mesons, adding a free parameter that adjusts the spectrum and improves agreement with QCD phenomenology, while maintaining key asymptotic behaviors.

Contribution

A new exactly solvable generalization of the soft wall model with an adjustable intercept parameter, enhancing the model's phenomenological accuracy.

Findings

The model's spectrum can be tuned to match experimental data.

The new parameter aligns well with QCD Operator Product Expansion.

Mass splitting between vector and axial mesons emerges naturally.

Abstract

We develop an exactly solvable generalization of the soft wall holographic model for the vector mesons. The generalization preserves the ultraviolet and infrared asymptotics of the soft wall model and contains an additional free parameter. This new parameter provides an arbitrary intercept in the Regge like spectrum of radial excitations and leads to a substantial modification of asymptotic expansion of the vector correlator at large momentum. The matching to the Operator Product Expansion from QCD allows to estimate the value of the new parameter which is shown to be in a good agreement with the phenomenology. In addition, the mass splitting between the vector and axial mesons arises naturally via the opposite sign of the introduced contribution to the intercept.