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Encounters between spherical galaxies II: systems with dark halo

A. C. Gonzalez-Garcia·T. S. van Albada
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Abstract

We performe N-body simulations of encounters between spherical systems surrounded by a spherical halo. Following a preceding paper with a similar aim, the initial systems include a spherical Jaffe model for the luminous matter and a Hernquist model for the halo. The merger remnants from this sample are mainly slowly rotating, prolate spheroids with a radially anisotropic velocity distribution. The results are compared with real-life ellipticals and with the models without halo in paper I. We argue that elliptical galaxies with evidence of dark matter could be formed in the field via a merger of spheroids surrounded by a dark matter halo, while ellipticals with no evidence of dark matter might be formed via a merger of two spheroids in a cluster.

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A. C. Gonzalez-Garcia, T. S. van Albada. 2005-06-01. Encounters between spherical galaxies II: systems with dark halo. https://doi.org/10.1111/j.1365-2966.2005.09243.x

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