Mesons in marginally deformed AdS/CFT

We study the embedding of spacetime filling D7–branes in β–deformed backgrounds which, according to the AdS/CFT dictionary, corresponds to flavoring β–deformed N = 4 super Yang–Mills. We consider supersymmetric and more general non–supersymmetric three parameter deformations. The equations of motion for quadratic fluctuations of a probe D7–brane wrapped on a deformed three–sphere exhibit a non–trivial coupling between scalar and vector modes induced by the deformation. Nevertheless, we manage to solve them analytically and find that the mesonic mass spectrum is discrete, with a mass gap and a Zeeman–like splitting occurs. Finally we propose the action for the dual field theory as obtained by ∗–product deformation of super Yang–Mills with fundamental matter.