Related papers: On the Fundamental Properties of Dynamically Hot G…
Dissipative dark matter, such as mirror dark matter and related hidden sector dark matter candidates, requires an energy source to stabilize dark matter halos in spiral galaxies. It has been proposed previously that supernovae could be the…
Studies of the Fundamental Plane of early-type galaxies, from small to intermediate redshifts, are often carried out under the guiding principle that the Fundamental Plane reflects the existence of an underlying mass-luminosity relation for…
The origin of equilibrium gravitational configurations is sought in terms of the stability of their trajectories, as described by the curvature of their Lagrangian configuration manifold of particle positions --- a context in which subtle…
Stellar and galactic systems are objects in dynamical equilibrium that are composed of ordinary baryonic matter hypothetically embedded in extended dominant dark matter halos. Our aim is to investigate the scaling relations and…
A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…
The paper confirms the existence of a special configuration (among the infinite number of virial states) which a B stellar(Baryonic) component may assume inside a given D dark halo potential well.This satisfies the d'Alembert Principle of…
Within the mirror dark matter model and dissipative dark matter models in general, halos around galaxies with active star formation (including spirals and gas rich dwarfs) are dynamical: they expand and contract in response to heating and…
We review the origin and structure of hot (cooling flow) gas in elliptical galaxies. X-ray observations can be used to determine the stellar mass to light ratio, the mass profiles of dark matter halos, and the interstellar magnetic field.…
We carry out numerical simulations of dissipationless major mergers of elliptical galaxies using initial galaxy models that consist of a dark matter halo and a stellar bulge with properties consistent with the observed fundamental plane. By…
Motivated by present indirect evidences that galaxies are surrounded by dark matter halos, we investigate whether their physical properties can be described by a formulation of the virial theorem which explicitly takes into account the…
Dynamical properties of two-component galaxy models whose stellar density distribution is described by a gamma-model while the total density distribution has a pure r^(-2) profile, are presented. The orbital structure of the stellar…
Why do galactic bars rotate with high pattern speeds, when dynamical friction should rapidly couple the bar to the massive, slowly rotating dark halo? This longstanding paradox may be resolved by considering the dynamical interactions…
The rotation curves of dark matter dominated dwarf galaxies are analysed. The observations show that dark matter halos represent a one-parameter family with self similar density profiles. The global halo parameters, like total mass and…
A simple way of explaining dark matter without modifying known Standard Model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. We consider a hidden sector…
Dynamically hot stellar systems, whether star clusters or early-type galaxies, follow well-defined scaling relations over many orders of magnitudes in mass. These fundamental plane relations have been subject of several studies, which have…
We simulate the dynamical, chemical, and spectro-photometric evolution of dwarf and normal elliptical galaxies embedded in a dark matter halo, using a three-dimensional N-body/SPH simulation code. For the forming dwarf elliptical galaxies,…
There are two families of luminous elliptical galaxies: cusp galaxies, with steep central surface-brightness profiles, and core galaxies, whose surface-brightness profiles have flat central cores. Thermal evaporation of accreted cold gas by…
The structure and dark matter halo core properties of dwarf spheroidal galaxies (dSphs) are investigated. A double-isothermal model of an isothermal stellar system, embedded in an isothermal dark halo core provides an excellent fit to the…
Dynamical modeling and strong lensing data indicate that the total density profiles of early-type galaxies are close to isothermal, i.e., rho_tot ~ r^gamma with gamma approx -2. To understand the origin of this universal slope we study a…
We examine two extreme models for the build-up of the stellar component of luminous elliptical galaxies. In one case, we assume the build-up of stars is dissipational, with centrally accreted gas radiating away its orbital and thermal…