A dynamical soft-wall holographic QCD model for chiral symmetry breaking and linear confinement

摘要

A self-consistent dynamical soft-wall holographic QCD model is formulated in the framework of graviton–dilaton–scalar system, which can realize both chiral symmetry breaking and confinement, two of the most important phenomena of QCD. The scalar field corresponds to the quark–antiquark condensate and can explain the property of chiral dynamics. The quadratic dilaton background field ?=μ2z2 as in the original soft-wall model can accommodate two aspects in the manifestation of color confinement, i.e. the Regge spectra of hadrons and the linear potential between quarks. It is observed that both the slope of the Regge spectra and the string tension of the quark potential are proportional to μ2. More interesting observation is that the best fitted value of μ is around the dynamical gluon mass extracted from lattice data. It is also shown that the negative dilaton background ?=?μ2z2 can be safely excluded in this framework.