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Dwarf Spheroidal Satellite Galaxies and the Galactic Tidal Field

Pavel Kroupa
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Abstract

The Milky Way is surrounded by nine or more dwarf-spheroidal (dSph) satellite galaxies that appear to consist primarily of dark matter. Here I summarise research that shows that initially spherical bound low-mass satellites without dark matter, that are on orbits within a massive Galactic dark corona, can evolve into remnants that are non-spherical, have a non-isotropic velocity dispersion tensor and are not in virial equilibrium, but are bright enough for sufficiently long times to be mistaken for dark-matter dominated dSph galaxies.

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Pavel Kroupa. 1996-12-03. Dwarf Spheroidal Satellite Galaxies and the Galactic Tidal Field. https://arxiv.org/abs/astro-ph/9612028

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