Abstract
After reviewing several aspects about the thermodynamics of self-gravitating systems that undergo the evaporation (escape) of their constituents, some recent results obtained in the framework of fermionic King model are applied here to the analysis of galactic halos considering warm dark matter (WDM) particles. According to the present approach, the reported structural parameters of dwarf galaxies are consistent with the existence of a WDM particle with mass in the keV scale. Assuming that the dwarf galaxy Willman 1 belongs to the region III of fermionic King model (whose gravothermal collapse is a continuous phase transition), one obtains the interval 1.2 keV ≤ m ≤ 2.6 keV for the mass of WDM particle. This analysis improves previous estimates by de Vega and co-workers [Astropart. Phys. 46 (2013) 14–22] considering both the quantum degeneration and the incidence of the constituents evaporation. This same analysis evidences that most of galaxies are massive enough to undergo a violent gravothermal collapse (a discontinuous microcanonical phase transition) that leads to the formation of a degenerate core of WDM particles. It is also suggested that quantum-relativistic processes governing the cores of large galaxies (e.g., the formation of supermassive black holes) are somehow related to the gravothermal collapse of the WDM degenerate cores when the total mass of these systems are comparable to the quantum-relativistic characteristic mass Mc=ℏc/G3/2m−2≃1012M⊙ obtained for WDM particles with mass m in the keV scale. The fact that a WDM particle with mass in the keV scale seems to be consistent with the observed properties of dwarf and large galaxies provides a strong support to this dark matter candidate.
Highlights
The thermodynamics of astrophysical systems is hallmarked by the incidence of a longrange interaction like Newtonian gravitation
I shall discuss some connections concerning the formation of degenerate core via gravothermal collapse, the supper-massive black holes that are reported to exist at the center of galaxies and the existence of warm dark matter (WDM) particles with mass in the keV scale
I have reviewed different aspects about the thermodynamics of astrophysical systems that undergo the evaporation of their constituents
Summary
The thermodynamics of astrophysical systems is hallmarked by the incidence of a longrange interaction like Newtonian gravitation. In the same fashion that King model is one of possible γ-exponential models that account for the incidence of evaporation for classical self-gravitating systems, the fermionic King model is just one of possible models that describe evaporation effects for systems of self-gravitating fermions Such bounds will depend on the concrete truncation of one-body distribution function at the escape energy εc, which means that this problem far to be fully solved in the present study. I shall return to this question at the end of conclusion section
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
