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arXiv · astro-ph/0406563

Distribution of mass in galaxy cluster CL0024 and the particle mass of dark matter

Abstract

We study in details the distribution of mass in galaxy cluster CL0024+1654 inferred using the method of strong gravitational lensing by Tyson {\it et al.} (1998). We show that a linear correlation exists between total, visible and dark matter distributions on log-log scale with consistent coefficients. The shape and parameters of log-log-linear correlation are not affected significantly whether one uses projected or volume mass densities but is consistent with $κ=2-5$ visible/dark ratio. We also show and analyze in depth so called alignment properties of the above-mentioned profiles. We show that log-log-linear correlation and alignments can all be understood in terms of thermodynamic/hydrodynamic equilibrium with gravitational potential growing almost linearly in the region of interest. We then analyze the hypothesis of thermal equilibrium on the base of the existing data about CL0024 cluster. If the presence of log-log-linear correlation and alignments were interpreted thermodynamically, this would indicate the mass of the dark matter particle 2-5 times smaller than that of atomic hydrogen, thus giving range for the mass of dark matter particle between 200MeV and 1000MeV.

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Yuriy Mishchenko, Chueng-Ryong Ji. 2004-06-24. Distribution of mass in galaxy cluster CL0024 and the particle mass of dark matter. https://arxiv.org/abs/astro-ph/0406563

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