Eur. Phys. J. C (2010) 66: 187-196
https://doi.org/10.1140/epjc/s10052-010-1239-0

Regular Article - Theoretical Physics

Confront holographic QCD with Regge trajectories of vectors and axial-vectors

¹ Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
² Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, Beijing, China
³ Department of Physics, University of Toronto, Toronto, Canada
⁴ Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
⁵ Department of Electrophysics, National Chiao-Tung University, Hsinchu, Taiwan
⁶ Physics Division, National Center for Theoretical Sciences, Hsinchu, Taiwan

^* e-mail: hesong@ihep.ac.cn

Received: 7 May 2009
Revised: 4 November 2009
Published online: 15 January 2010

Abstract

By matching the predictions of the Dp–Dq soft-wall model in type II superstring theory with the spectra of vector and axial-vector mesons, we show the dependence of the Regge trajectories parameters on the metric parameters of the model. From the experimental results of Regge parameters for vector mesons, it is found that the D3 background brane with both q=5 and q=7 probe brane and D4 background brane with q=4 probe brane are close to the realistic holographic QCD. We also discuss how to realize chiral symmetry breaking in the vacuum and asymptotic chiral symmetry restoration in high excitation states. We find that the constant component of the 5-dimension mass square of axial-vector mesons plays an efficient role to realize the chiral symmetry breaking, and a small negative z ⁴ correction in the 5-dimension mass square is helpful to realize the chiral symmetry restoration in high excitation states.