Decaying sterile neutrinos as a heating source in the Milky Way centre

Recent Chandra and XMM–Newton observations indicate that there are two-temperature components ( T ～ 8 keV, 0.8 keV) of the diffuse X-rays emitted from deep inside the centre of Milky Way. We show that this can be explained by the existence of sterile neutrinos, which decay to emit photons that can be bound-free absorbed by the isothermal hot-gas particles in the centre of Milky Way. The model can account for a stable configuration of the two-temperature components hot gas naturally as well as the energy needed to maintain the ～8 keV temperature in the hot gas. The predicted sterile neutrino mass is between 16–18 keV.