An improved model of vector mesons in holographic QCD

Abstract

We analyze the sector of dimension-three vector meson operators in the "hard wall" model of holographic QCD, including the vector and axial currents, dual to gauge fields in the bulk, and the tensor operator $\bar{\psi}\sigma^{\mu\nu}\psi$, dual to a two-form field satisfying a complex self-duality condition. The model includes the effect of chiral symmetry breaking on vector mesons, that involves a coupling between the dual gauge field and the two-form field. We compute the leading logarithmic terms in the operator product expansion of two-point functions and the leading non-perturbative contribution to the tensor-vector correlator. The result is consistent with the operator product expansion of QCD. We also study the spectrum of vector mesons numerically.