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Related papers: Modelling elliptical galaxies: phase-space constra…

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We present here a self-consistent, tridimensional model of a disc galaxy composed by a number of ellipsoidal distributions of matter having different flattening and density profile. The model is self-consistent and takes into account the…

Astrophysics · Physics 2009-09-25 E. Pignatelli , G. Galletta

N-body simulations of dark matter halos show that the density is cusped near the center of the halo. The density profile behaves as $r^{-\gamma}$ in the inner parts, where $\gamma \simeq 1$ for the NFW model and $\gamma \simeq 1.5$ for the…

Astrophysics · Physics 2009-06-23 Ding Ma , Ping He

This paper presents two families of phase-space distribution functions (DFs) that generate scale-free spheroidal mass densities in scale-free spherical potentials. The `case I' DFs are anisotropic generalizations of the flattened f(E,L_z)…

Astrophysics · Physics 2015-06-24 Jos H. J. de Bruijne , Roeland P. van der Marel , P. Tim de Zeeuw

We add to the lore of spherical, stellar-system models a two-parameter family with an anisotropic velocity dispersion, and a central point mass (``black hole''). The ratio of the tangential to radial dispersions, is constant--and…

Astrophysics · Physics 2009-10-28 Mordehai Milgrom

We have investigated the stability of a set of non-rotating anisotropic spherical models with a phase-space distribution function of the Osipkov-Merritt type. The velocity distribution in these models is isotropic near the center and…

Astrophysics · Physics 2009-10-30 Andres Meza , Nelson Zamorano

In this paper we present new chemo-spectro-photometric models of elliptical galaxies in which infall of primordial gas is allowed to occur. They aim to simulate the collapse of a galaxy made of two components, i.e. luminous material and…

Astrophysics · Physics 2007-05-23 R. Tantalo , C. Chiosi , A. Bressan , F. Fagotto

Simple analytical models, such as the Hernquist model, are very useful tools to investigate the dynamical structure of galaxies. Unfortunately, most of the analytical distribution functions are either isotropic or of the Osipkov-Merritt…

Astrophysics · Physics 2009-11-07 Maarten Baes , Herwig Dejonghe

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…

Astrophysics · Physics 2009-11-10 Maarten Baes , Herwig Dejonghe

We study profiles of mass density, velocity dispersion (VD), and their combination using $\sim 2000$ nearly spherical and rotation-free SDSS galaxies. For observational stellar mass density $\rho_{\star}(r)$ we consider a range of dark…

Astrophysics of Galaxies · Physics 2017-01-04 Kyu-Hyun Chae

A tensor virial approach is used to construct detailed models of 22 flattened ellipticals. The models are combined with the new observational data: extended surface brightness distributions, the profiles of isophotes flattening and their…

Astrophysics of Galaxies · Physics 2020-01-29 B. P. Kondratyev , E. N. Kireeva

Recently, two-component spherical galaxy models have been presented, where the stellar profile is described by a Jaffe law, and the total density by another Jaffe law, or by an $r^{-3}$ law at large radii. We extend these two families to…

Astrophysics of Galaxies · Physics 2020-11-04 L. Ciotti , A. Mancino , S. Pellegrini , A. Ziaee Lorzad

A growing body of observational evidence suggests that the luminosity, photometric shape and amount of rotational or anisotropical support in elliptical galaxies may provide vital clues to how they formed. Elliptical galaxies appear to fall…

Astrophysics · Physics 2008-11-26 B. Rothberg , R. D. Joseph

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…

Astrophysics · Physics 2009-11-07 Yan Guo , Gerhard Rein

For a wide class of self-gravitating systems, we show that if the density is cusped like 1/r^{gamma} near the center, then the limiting value of the anisotropy parameter beta = 1 - <v_T^2>/(2<v_r^2>) at the center may not be greater than…

Astrophysics · Physics 2007-05-23 J. An , N. W. Evans

Massive early-type galaxies are observed to lie on the Mass Plane (MP), a two-dimensional manifold in the space of effective radius R_e, projected mass M_p (measured via strong gravitational lensing) and projected velocity dispersion sigma…

Astrophysics · Physics 2009-11-13 C. Nipoti , T. Treu , A. S. Bolton

We present a new method of constraining the mass and velocity anisotropy profiles of galaxy clusters from kinematic data. The method is based on a model of the phase space density which allows the anisotropy to vary with radius between two…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Radoslaw Wojtak , Ewa L. Lokas , Gary A. Mamon , Stefan Gottloeber

Elements of kinematical and dynamical modeling of elliptical galaxies (Es) are presented. In projection, NFW models resemble Sersic models, but with a very narrow range of shapes (m=3+/-1). The total density profile of Es cannot be NFW-like…

Astrophysics · Physics 2009-11-11 G. A. Mamon , E. Lokas , A. Dekel , F. Stoehr , T. J. Cox

An iterative approach is used to construct spherically symmetric equilibrium models with an anisotropic velocity distribution. The potentialities of the method have been tested on models with known distribution functions, the…

Astrophysics · Physics 2009-11-13 N. Ya. Sotnikova , S. A. Rodionov

This paper constructs two immediate extensions of the existing anisotropic solutions in the context of Einstein-Maxwell framework by employing minimal geometric deformation. To achieve this, we assume a static spherical interior initially…

General Relativity and Quantum Cosmology · Physics 2023-10-03 M. Sharif , Tayyab Naseer

We present a systematic analysis of the constraints $\sigma_\gamma$ on the mass profile slope $\gamma$ obtainable when fitting a singular power-law ellipsoid model to a typical strong lensing observation of an extended source. These results…

Astrophysics of Galaxies · Physics 2020-06-24 Conor M. O'Riordan , Stephen J. Warren , Daniel J. Mortlock