Related papers: Triaxial Galaxies with Cusps
We present a family of spherical models for elliptical galaxies and bulges consisting of a stellar component and a central black hole. All models in this family share the same stellar density profile, which has a steep central cusp. The…
Standard cosmology has many successes on large scales, but faces some fundamental difficulties on small, galactic scales. One such difficulty is the cusp/core problem. High resolution observations of the rotation curves for dark matter…
Orbital motion in triaxial nuclei with central point masses, representing supermassive black holes, is investigated. The stellar density is assumed to follow a power law, rho ~ 1/r^gamma, with gamma=1 or gamma=2. At low energies the motion…
While N-body simulations testify for a cuspy profile of the central region of the dark matter haloes, observations favor a shallow, cored density profile of the central region of, at least, some spiral galaxies and dwarf spheroidals. We…
Recent studies have shown that massive quiescent galaxies at high redshift are much more compact than present-day galaxies of the same mass. Here we compare the radial stellar density profiles and the number density of a sample of massive…
We test the hypothesis that globular clusters form in supergiant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that such large, dense, and cold gas clouds assemble naturally in current hierarchical models…
Rotation curves of galaxies probe their total mass distributions, including dark matter. Dwarf galaxies are excellent systems to investigate the dark matter density distribution, as they tend to have larger fractions of dark matter compared…
We present observational evidence of the impact of triaxiality on radial profiles that extend to 40 Mpc from galaxy cluster centres in optical measurements. We perform a stacked profile analysis from a sample of thousands of nearly relaxed…
We use numerical simulations to investigate the cusp at the centre of elliptical galaxies, due to the slow growth of a super-massive black hole. We study this problem for axisymmetric models of galaxies, with or without rotation. The…
We present a technique for constructing equilibrium triaxial N-body haloes with nearly arbitrary density profiles, axial ratios and spin parameters. The method is based on the way in which structures form in hierarchical cosmological…
In the past two decades, it has been established by high-resolution observations of early-type galaxies that their nuclear surface brightness and corresponding stellar mass densities are characterized by cusps. In this paper, we present a…
We propose an analytical method to describe a matter density profile near a galaxy center. The description is based on the study of the distribution function of particles over possible trajectories. We establish a relation between the…
The stellar surface mass density profiles at the centers of typical ~L* and lower-mass spheroids exhibit power law 'cusps' with $\Sigma \propto R^(-n)$, where 0.5<n<1 for radii ~1-100 pc. Observations and theory support models in which…
Weak gravitational lensing studies of galaxy clusters often assume a spherical cluster model to simplify the analysis, but some recent studies have suggested this simplifying assumption may result in large biases in estimated cluster masses…
We present uniformly measured star formation histories (SFHs) of 60 nearby (D~4Mpc) dwarf galaxies based on CMDs of resolved stellar populations from images taken with HST as part of the ACS Nearby Galaxy Survey Treasury program (ANGST).…
We have analyzed the galaxy number density and luminosity density profiles of rich clusters of galaxies from redshifts z=0 to z=0.5. We show that the luminosity profile computed with bright galaxies is significantly cusped in the center of…
Early observations with JWST have led to the discovery of an unexpected large density (stellar mass density $\rho_*\approx 10^{6}\,M_{\odot}\,Mpc^{-3}$) of massive galaxies (stellar masses $M_*\geq 10^{10.5}M_{\odot}$) at extremely high…
We study the history from $z\sim2$ to $z\sim0$ of the stellar mass assembly of quiescent and star-forming galaxies in a spatially resolved fashion. For this purpose we use multi-wavelength imaging data from the Hubble Space Telescope (HST)…
A method is developed to evaluate the magnifications of the images of galaxies with lensing potentials stratified on similar concentric ellipses. A simple contour integral is provided which enables the sums of the magnifications of even…
We construct stable axially symmetric models of elliptical galaxies. The particle density on phase space for these models depends monotonically on the particle energy and on the third component of the angular momentum. They are obtained as…