Anomalous $A{V}^{\ast }V$ vertex function in the soft-wall holographic model of QCD

Abstract

We consider the vertex function of two vector and one axial-vector currents using the soft-wall holographic model of QCD with the Chern-Simons term. Two structure functions $w_L$ and $w_T$ describe such a vertex in the special case in which one of the two vector currents corresponds to an on-shell soft photon. We briefly review the QCD results for these functions, obtained from triangular loop diagrams with quarks having mass $m_q=0$ or $m_q\ne 0$, we compute $w_L$ and $w_T$ in the soft-wall model and compare the outcome to the QCD findings. We also calculate and discuss the two-point ${\Pi }_{VV}-{\Pi }_{AA}$ correlation function, together with a few low-energy constants, which turn out to be close to the QCD results.

Comments: LaTeX, 29 pages. Matches the published version