3.55 keV X-ray line signal from excited dark matter in radiative neutrino model

We study an exciting dark matter scenario in a radiative neutrino model to explain the X-ray line signal at 3.55 keV3.55 keV recently reported by XMN-Newton X-ray observatory using data of various galaxy clusters and Andromeda galaxy. We show that the required large cross section for the up-scattering process to explain the X-ray line can be obtained via the resonance of the pseudo-scalar. Moreover, this model can be compatible with the thermal production of dark matter and the constraint from the direct detection experiment.