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arXiv · 0903.2755

Analytical galactic models with mild stellar cusps

T. Rindler-Daller
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Abstract

In the past two decades, it has been established by high-resolution observations of early-type galaxies that their nuclear surface brightness and corresponding stellar mass densities are characterized by cusps. In this paper, we present a new spherical analytical model family describing mild cuspy centres. We study isotropic and anisotropic models of Osipkov-Merritt type. It is shown that the associated distribution functions and intrinsic velocity dispersions can be represented analytically in a unified way in terms of hypergeometric series, allowing thus a straightforward comparison of these important global quantities for galaxies having underlying mass densities which may differ significantly in their degree of central cuspiness or radial falloff.

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T. Rindler-Daller. 2009-03-20. Analytical galactic models with mild stellar cusps. https://doi.org/10.1111/j.1365-2966.2009.14760.x

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