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arXiv · 1010.2602

Dark Matter Halos: The Dynamical Basis of Effective Empirical Models

A. Lapi·A. Cavaliere
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Abstract

We investigate the dynamical basis of the classic empirical models (specifically, Sersic-Einasto and generalized NFW) that are widely used to describe the distributions of collisionless matter in galaxies. We submit that such a basis is provided by our α-profiles, shown to constitute solutions of the Jeans dynamical equilibrium with physical boundary conditions. We show how to set the parameters of the empirical in terms of the dynamical models; we find the empirical models, and specifically Sersic-Einasto, to constitute a simple and close approximation to the dynamical models. Finally, we discuss how these provide an useful baseline for assessing the impact of the small-scale dynamics that may modulate the density slope in the central galaxy regions.

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A. Lapi, A. Cavaliere. 2010-10-13. Dark Matter Halos: The Dynamical Basis of Effective Empirical Models. https://doi.org/10.1155/2011%2F903429

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