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Approximate dynamics of dark matter ellipsoids

G. S. Bisnovatyi-Kogan·O. Yu. Tsupko
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Abstract

The collapse of non-collisional dark matter and the formation of pancake structures in the Universe are investigated approximately. Collapse is described by a system of ordinary differential equations, in the model of a uniformly rotating, three-axis, uniform density ellipsoid. Violent relaxation, mass and angular momentum losses are taken into account phenomenologically. The formation of the equilibrium configuration, secular instability and the transition from a spheroid to a three-axis ellipsoid are investigated numerically and analytically in this dynamical model.

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G. S. Bisnovatyi-Kogan, O. Yu. Tsupko. 2005-12-12. Approximate dynamics of dark matter ellipsoids. https://doi.org/10.1111/j.1365-2966.2005.09614.x

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