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Dark Matter at the Center and in the Halo of the Galaxy

Neven Bilic·Gary B. Tupper·Raoul D. Viollier
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Abstract

All presently known stellar-dynamical constraints on the size and mass of the supermassive compact dark object at the Galactic center are consistent with a ball of self-gravitating, nearly non-interacting, degenerate fermions with mass between 76 and 491 keV, for degeneracy factor g=2. Sterile neutrinos of 76 keV mass, which are mixed with at least one of the active neutrinos with a mixing angele ~10^{-7}, are produced in about the right amount in the early Universe by incoherent resonant and non-resonant scattering of active neutrinos having asymmetry of ~0.01. The former process yields sterile neutrinos with a quasi-degenerate spectrum while the latter leads to a thermal spectrum. As the production mechanism of the sterile neutrino is consistent with the constraints from large scale structure formation, core collapse supernovae, and diffuse X-ray background, it could be the dark matter particle of the Universe.

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Neven Bilic, Gary B. Tupper, Raoul D. Viollier. 2003-10-10. Dark Matter at the Center and in the Halo of the Galaxy. https://arxiv.org/abs/astro-ph/0310294

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