All-sky Limits on Sterile Neutrino Galactic Dark Matter Obtained with SRG/ART-XC after Two Years of Operations

Dark matter sterile neutrinos radiatively decay in the Milky Way, which can be tested with searches for almost monochromatic photons in the x-ray cosmic spectrum. We analyse the data of SRG/ART-XC telescope operated for two years in the all-sky survey mode. With no significant hints in the Galactic diffuse x-ray spectrum we explore models with sterile neutrino masses in 12-40 keV range and exclude corresponding regions of sterile-active neutrino mixing.