1 research outputs found
Stellar polytropes and Navarro-Frenk-White halo models: comparison with observations
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) and one which follows the SP description. Analyzing the dark matter
contents estimated by means of global physical parameters of galactic disks,
obtained from a sample of actual galaxies, with the ones of the unobserved dark
matter halos, we conclude that the SP model is favored over the NFW model in
such a comparison.Comment: 21 pages, 4 figures. Accepted for publication in the Journal of
Cosmology and Astroparticle Physic