2006/05/29 by Jesús Zavala, Jesus Zavala, Dario Nunez +5
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Statistical Mechanics and Entropy #astro-ph
paper · pdf · doi:10.1088/1475-7516/2006/06/008
published as JCAP 0606 (2006) 008 · 21 pages, 4 figures. Accepted for publication in the Journal of Cosmology and Astroparticle Physics
arxiv created 2006/05/29 · openalex publication_date 2006/06/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Motivated by the possible conflict between the Navarro–Frenk–White (NFW) model predictions for the dark matter contents of galactic systems and its correlation with baryonic surface density, we will explore an alternative paradigm for the description of dark matter halos. Such an alternative emerges from Tsallis' non-extensive thermodynamics applied to self-gravitating systems and leads to the so-called 'stellar polytrope' (SP) model. We consider that this could be a better approach to real structures rather than the isothermal model, given the fact that the first one takes into account the non-extensivity of energy and entropy present in these type of systems characterized by long-range interactions. We compare a halo based on the Navarro–Frenk–White (NFW) model and one which follows the SP description. Analysing the dark matter contents estimated by means of global physical parameters of galactic discs, obtained from a sample of actual galaxies, with the ones of the unobserved dark matter halos, we conclude that the SP model is favoured over the NFW model in such a comparison.