Hovhannes Grigoryan

Thomas Jefferson National Accelerator Facility

Holographic dual model of QCD as an alternative tool for studying the strong interactions at low energies

At low energies, QCD is a strongly interacting theory, and nonperturbative methods such as DSE formalism and lattice QCD are developed to study it. Here, we discuss an alternative approach for performing nonperturbative calculations inspired from the AdS/CFT correspondence which relates the strongly interacting theory in 4D and the weakly interacting theory in 5D. This correspondence allows to find the n-point functions of the strongly coupled 4D theory from the perturbative calculations in 5D. Working in the framework of the AdS/QCD model, we develop a formalism to calculate various form factors of vector and pseudoscalar mesons. From the form factors of the rho-meson we extract the values of such observables as electric charge radius, magnetic and quadrupole moments and compare these with the results using DSE formalism and lattice QCD. For the pion, we express the electric charge radius and the decay constant in terms of the two parameters of the theory and compare these with experiment, ChPT and NJL model. Finally, we show how to incorporate the anomalous pion decay into the holographic model and calculate the pi → gamma-gamma form factor.

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