Infrared-improved soft-wall AdS/QCD model for mesons

We construct and investigate an infrared-improved soft-wall AdS/QCD model for mesons. Both linear confinement and chiral symmetry breaking of low energy QCD are well characterized in such an infrared-improved soft-wall AdS/QCD model. The model enables us to obtain a more consistent numerical prediction for the mass spectra of resonance scalar, pseudoscalar, vector, and axial-vector mesons. In particular, the predicted mass for the lightest ground state scalar meson shows good agreement with the experimental data. The model also provides a remarkable check for the Gell-Mann–Oakes–Renner relation and a sensible result for the space-like pion form factor