Quark Mass Dependence of Hadron Spectrum in Holographic QCD

TL;DR

This paper calculates how quark masses affect baryon and meson spectra within the holographic QCD Sakai-Sugimoto model, providing results consistent with lattice QCD and predicting specific mass shifts for various particles.

Contribution

It introduces a perturbative method to compute quark mass-induced shifts in hadron spectra in holographic QCD, aligning with lattice results and offering new predictions.

Findings

Ground state nucleon mass shift: 4.1 m_π^2 [GeV^{-1}]

Predicted shift for N(1535) and Delta: 4.1 m_π^2 [GeV^{-1}]

Larger shift for Roper N(1440): 7.7 m_π^2 [GeV^{-1}]

Abstract

We compute a shift of baryon mass spectra due to quark masses in perturbation, in Sakai-Sugimoto model of holographic QCD. We find the shift for the ground state nucleons to be \delta M = 4.1 m_{\pi}^2 [GeV^{-1}], which is consistent with the current lattice QCD result. We predict the same value of the shift for N(1535) and Delta, while a larger value 7.7 m_{\pi}^2 [GeV^{-1}] for Roper N(1440). We also present some evidences that the shifts of the vector meson masses are suppressed in the large 't Hooft coupling limit.