Recent astronomical results of dark matter searching

Abstract

Two new astronomical results of the dark matter (DM) halo influence on physical processes in it are presented. We discuss Cherenkov radiation in the a galactic DM halo and the DM halo presentation as a dispersional gravitational lens. It is shown that the temperature of Cherenkov radiation in the X-ray range is about T ∼ 10 −6 K, which is close to the temperature fluctuations of cosmic background radiation ΔT ∼ 10 −5 K and is thus at the threshold of modern astronomical measurements. Based on the time variability of the DM state parameter, we have suggested the concept of a dispersional gravitational lens. A dependence of the DM halo refractive index on its own global oscillations was found. It is shown that DM may oscillate with the frequency ωDM ≥ 10 −15 Hz. Hence, it is possible to talk about superweak DM oscillations and the existence of very cold DM particles whose mass is larger than mVCDM ≥ 10 −42 eV.