Fermi gamma ray line at 130 GeV from axion-mediated dark matter

We consider a singlet Dirac fermion with Peccei-Quinn (PQ) symmetry as dark matter. A singlet complex scalar is introduced to mediate between dark matter and the Standard Model through Higgs portal interaction and electroweak PQ anomalies. We show that a resonant annihilation of dark matter with axion mediation can explain the monochromatic photon line of the Fermi Large Area Telescope data at 130GeV by anomaly interactions while the annihilation cross section with Higgs portal interaction is p-wave suppressed. We discuss the interplay between the direct detection of the fermion dark matter and the collider search of Higgs-like scalars. We also present an ultraviolet completion of the dark matter model into the Next-to-Minimal Supersymmetric Standard Model with PQ symmetry.