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Mapping Substructures in Dark Matter Halos

Alexander Knebe·Stuart P. D. Gill·Daisuke Kawata·Brad K. Gibson
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Abstract

We present a detailed study of the real and integrals-of-motion space distributions of a satellite obtained from a self-consistent high-resolution simulation of a galaxy cluster and re-simulated using various analytical halo potentials. We found that the disrupted satellite appears as a coherent structure in integrals-of-motion space in all models (``live'' and analytical potential) although the distribution is significantly smeared for the live host halo. Further the primary mechanism for this smearing is the mass growth of the host, which changes both the energy and angular momentum of the satellite debris. Hence, this must be considered when searching for (stellar) streams with future observational experiments such as RAVE and GAIA.

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Alexander Knebe, Stuart P. D. Gill, Daisuke Kawata, Brad K. Gibson. 2004-12-02. Mapping Substructures in Dark Matter Halos. https://doi.org/10.1111/j.1745-3933.2005.08666.x

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