2001/01/26 by Piero Ullio, Hongsheng Zhao, HongSheng Zhao +1 · 15 citations
Physics and Astronomy · #Astrophysics #Bulge #Center (category theory) #Cold dark matter #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Dark matter halo #Galactic Center #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Physics #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevd.64.043504
published as Phys.Rev. D64 (2001) 043504 · 11 pages, 6 figures
arxiv created 2001/01/26 · openalex publication_date 2001/07/20 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The past growth of the central black hole (BH) might have enhanced the density of cold dark matter halo particles at the galactic center. We compute this effect in realistic growth models of the present (2\ensuremath-3)\ifmmode×\else\texttimes\fi106M_\ensuremath\bigodot BH from a low-mass seed BH, with special attention to dynamical modeling in a realistic galaxy environment with merger and orbital decay of a seed BH formed generally outside the exact center of the halo. An intriguing ``very-dense spike'' of dark matter has been claimed in models of Gondolo and Silk with a density high enough to contradict with experimental upper bounds of neutralino annihilation radiation. This ``spike'' disappears completely or is greatly weakened when we include important dynamical processes neglected in their idealized or restrictive picture with cold particles surrounding an at-the-center zero-seed adiabatically growing BH. For the seed BH to spiral in and settle to the center within a Hubble time by dynamical friction, the seed mass must be at least a significant fraction of the present BH. Any subsequent at-the-center growth of the BH and steepening of the central Keplerian potential well can squeeze the halo density distribution only mildly, whether the squeezing happens adiabatically or instantaneously.