Massive Sterile Neutrinos For Dark Matter Halos

Abstract

This study pertains to an investigative analysis of the Ruffini-Arg uelles-Rueda (RAR) model of a self-gravitating gas of about 48 to 345 keV degenerate fermions that form a fully degenerate core, with and without considering the cutoff effects. These fermions are taken to provide the non-baryonic dark matter which lie outside the standard model of Particle Physics and are known as "sterile neutrinos" or "neutralinos". It assumes a degenerate Fermi core surrounded by a partially degenerate Fermi halo. We see if we get the cores collapsing into black holes in such a system enhancing the potential well of the degenerate fermions. In order to conduct an analysis, we use fermions of masses 48 keV , 56 keV , 100 keV , 200 keV , and 348 keV for the calculations. The density profiles and rotation curves show three remarkably different regimes: the quantum core, transition region from quantum to classical effects, and classical halo. We also check the results for masses below 48 keV . Latest research shows that at fermion mass 56 keV a compact core with mass and size close enough to that of Sgr A* is obtained, this gives an excellent explanation to the idea of considering a fermionic core as an alternative to Sgr A*.