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Harassment Origin for Kinematic Substructures in Dwarf Elliptical Galaxies?

A. C. Gonzalez-Garcia·J. A. L. Aguerri·M. Balcells
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Abstract

We have run high resolution N-body models simulating the encounter of a dwarf galaxy with a bright elliptical galaxy. The dwarf absorbs orbital angular momentum and shows counter-rotating features in the external regions of the galaxy. To explain the core-envelope kinematic decoupling observed in some dwarf galaxies in high-density environments requires nearly head-on collisions and very little dark matter bound to the dwarf. These kinematic structures appear under rather restrictive conditions. As a consequence, in a cluster like Virgo ~1% of dwarf galaxies may present counter-rotation formed by harassment.

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A. C. Gonzalez-Garcia, J. A. L. Aguerri, M. Balcells. 2005-08-29. Harassment Origin for Kinematic Substructures in Dwarf Elliptical Galaxies?. https://doi.org/10.1051/0004-6361%3A20052670

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