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Globular Clusters with Dark Matter Halos. II. Evolution in Tidal Field

Sergey Mashchenko·Alison Sills
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Abstract

In this second paper in our series, we continue to test primordial scenarios of globular cluster formation which predict that globular clusters formed in the early universe in the potential of dark matter minihalos. In this paper we use high-resolution N-body simulations to model tidal stripping experienced by primordial dark-matter dominated globular clusters in the static gravitational potential of the host dwarf galaxy. We test both cuspy Navarro-Frenk-White (NFW) and flat-core Burkert models of dark matter halos. Our primordial globular cluster with an NFW dark matter halo survives severe tidal stripping, and after 10 orbits is still dominated by dark matter in its outskirts. Our cluster with Burkert dark matter halo loses almost all its dark matter to tidal stripping, and starts losing stars at the end of our simulations. The results of this paper reinforce our conclusion in Paper I that current observations of globular clusters are consistent with the primordial picture of globular cluster formation.

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Sergey Mashchenko, Alison Sills. 2004-09-26. Globular Clusters with Dark Matter Halos. II. Evolution in Tidal Field. https://doi.org/10.1086/426133

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