Holographic QCD model for $N_f=4$

TL;DR

This paper develops a holographic QCD model for four flavors, incorporating scalar fields to describe light, heavy, and mixed mesons, successfully matching experimental meson spectra and allowing different Regge slopes for light and heavy mesons.

Contribution

It introduces a novel holographic QCD model with separate scalar fields for light and heavy flavors, enabling accurate meson spectrum predictions and adjustable Regge slopes.

Findings

Meson spectra match PDG data

Different Regge slopes for light and heavy mesons achieved

Model successfully describes light-heavy mesons

Abstract

We establish a holographic QCD model for four flavors, where a light scalar field $X$ and a heavy scalar field $H$ are introduced, separately. The $H$ field is responsible for the breaking of $SU(N_f=4)$ to $SU(N_f=3)$. The ground state and its Regge excitation of meson spectra in the light flavor sector and heavy flavor sector as well as the ligh-heavy mesons are well in agreement with the Particle data group (PDG). Due to the additional introduction of the $H$ field in the model, different Regge slopes for light and heavy mesons can be achieved.