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.