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The Orbital Structure of Dark Matter Halos with Gas

Andisheh Mahdavi
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Abstract

With the success of the Chandra and XMM missions and the maturation of gravitational lensing techniques, powerful constraints on the orbital structure of cluster dark matter halos are possible. I show that the X-ray emissivity and mass of a galaxy cluster uniquely specify the anisotropy and velocity dispersion profiles of its dark matter halo. I consider hydrostatic as well as cooling flow scenarios, and apply the formalism to the lensing cluster CL0024+16 and the cooling flow cluster Abell 2199. In both cases, the model predicts a parameter-free velocity dispersion profile that is consistent with independent optical redshift surveys of the clusters.

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Andisheh Mahdavi. 2000-08-09. The Orbital Structure of Dark Matter Halos with Gas. https://doi.org/10.1086/318286

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