arXiv 0801.25042008-01-16astro-phcond-mat.stat-mech

Simulated Dark-Matter Halos as a Test of Nonextensive Statistical Mechanics

Chloé Féron, Jens Hjorth

备注：: Accepted for publication in Physical Review E
发表信息：: Phys.Rev.E77:022106,2008
DOI：: 10.1103/PhysRevE.77.022106

英文摘要：

In the framework of nonextensive statistical mechanics, the equilibrium structures of astrophysical self-gravitating systems are stellar polytropes, parameterized by the polytropic index n. By careful comparison to the structures of simulated dark-matter halos we find that the density profiles, as well as other fundamental properties, of stellar polytropes are inconsistent with simulations for any value of n. This result suggests the need to reconsider the applicability of nonextensive statistical mechanics (in its simplest form) to equilibrium self-gravitating systems.

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