On the core-halo distribution of dark matter in galaxies

TL;DR

This paper models dark matter distribution in galaxies using self-gravitating fermions, revealing a core-halo structure with quantum and classical regimes that explain galaxy rotation curves.

Contribution

It introduces a comprehensive quantum-statistical model of dark matter halos, linking core properties to galaxy rotation curves within general relativity.

Findings

Inner core governed by quantum degeneracy

Extended plateau with quantum corrections

Outer region with classical $ ho \,\propto r^{-2}$ profile

Abstract

We investigate the distribution of dark matter in galaxies by solving the equations of equilibrium of a self-gravitating system of massive fermions (`inos') at selected temperatures and degeneracy parameters within general relativity. Our most general solutions show, as a function of the radius, a segregation of three physical regimes: 1) an inner core of almost constant density governed by degenerate quantum statistics; 2) an intermediate region with a sharply decreasing density distribution followed by an extended plateau, implying quantum corrections; 3) an asymptotic, $\rho\propto r^{-2}$ classical Boltzmann regime fulfilling, as an eigenvalue problem, a fixed value of the flat rotation curves. This eigenvalue problem determines, for each value of the central degeneracy parameter, the mass of the ino as well as the radius and mass of the inner quantum core. Consequences of this alternative approach to the central and halo regions of galaxies, ranging from dwarf to big spirals, for SgrA*, as well as for the existing estimates of the ino mass, are outlined.