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Dynamics of Dark Matter Cusps

David Merritt·Milos Milosavljevic
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Abstract

Formation and disruption of dark-matter cusps are reviewed. Accumulation of baryons at the center of a halo can displace the dark matter, converting singular density cusps into low-density cores. The displaced mass can be of order 10 M_b with M_b the mass of the infalling population. If M_b is identified with the masses of the black holes currently observed at the centers of bright galaxies, predicted core radii are ~a few hundred pc. Other mechanisms, such as early mass outflow, may explain the large dark-matter cores in dwarf and low-surface-brightness galaxies. Predictions of dark matter annihilation radiation from the center of the Milky Way galaxy are shown to be strongly dependent on the galaxy's merger history.

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David Merritt, Milos Milosavljevic. 2002-05-09. Dynamics of Dark Matter Cusps. https://arxiv.org/abs/astro-ph/0205140

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