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Related papers: A Family of Models for Spherical Stellar Systems

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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 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

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

The dynamical properties of spherically symmetric galaxy models, where a Jaffe (1983) stellar density profile is embedded in a total mass density decreasing as $r^{-3}$ at large radii, are presented. The orbital structure of the stellar…

Astrophysics of Galaxies · Physics 2019-10-02 L. Ciotti , A. Mancino , S. Pellegrini

We first stress that any spherically symmetric galactic model whose integrated mass profile $M (r) \to 0$ as $r \to 0$ is physically consistent close to the centre only provided that the circular velocity $v_c (r) \to 0$ and the…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-20 Marco Roncadelli , Giorgio Galanti

We assemble and observe a sample of poor galaxy systems that is suitable for testing N-body simulations of hierarchical clustering (Navarro, Frenk, & White 1997; NFW) and other dynamical halo models (e.g., Hernquist 1990). We (1) determine…

Astrophysics · Physics 2009-10-31 A. Mahdavi , M. J. Geller , H. Boehringer , M. J. Kurtz , M. Ramella

Dynamical properties of spherically symmetric galaxy models where both the stellar and total mass density distributions are described by the Jaffe (1983) profile (with different scale-lenghts and masses), are presented. The orbital…

Astrophysics of Galaxies · Physics 2017-12-20 L. Ciotti , A. Ziaee Lorzad

A new class of models of stellar discs is introduced and used to build a self-consistent model of our Galaxy. The model is defined by the parameters that specify the action-based distribution functions (DFs) f(J) of four stellar discs…

Astrophysics of Galaxies · Physics 2023-01-25 James Binney , Eugene Vasiliev

We discuss the kinematical structure of a two-parameter family of isotropic models with a central black hole. The family contains the slope of the central density cusp and the relative black hole mass as parameters. Most of the basic…

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

A new two-parametric family of mass distribution for spherical stellar systems is considered. It generalizes families by Kuzmin, Veltmann (1972) and by An, Evans (2006). Steady velocity dispersions are found for these models by solving an…

Astrophysics of Galaxies · Physics 2010-03-02 Natalya Raspopova , Leonid Ossipkov

We demonstrate the existence of distribution functions that can be used to represent spherical massless cored stellar systems embedded in cuspy dark matter halos with constant mildly tangential velocity anisotropy. In particular, we derive…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Maarten A. Breddels , Amina Helmi

The properties of the analitycal phase--space distribution function of two-component spherical self-consistent galaxy models, where one density distribution follows the Hernquist profile, and the other a gamma=0 model, with different total…

Astrophysics · Physics 2007-05-23 L. Ciotti

A new potential is presented for spherical galaxies. The technique of the construction of our model is similar to that given by An and Evans. In a special case, its mass density becomes a special one of the Hernquist model. Another special…

Astrophysics of Galaxies · Physics 2025-03-11 Zhenglu Jiang , Zanchen Zhuo

We present a new analytical solution to the steady-state distribution of stars close to a central supermassive black hole of mass $M_{\bullet}$ in the center of a galaxy. Assuming a continuous mass function of the form $dN/dm \propto…

Astrophysics of Galaxies · Physics 2022-11-30 Itai Linial , Re'em Sari

It was recently demonstrated that imposing the condition $P_{r} = -\rho$ on the radial pressure of a galactic halo can lead to regular black-hole solutions for certain density profiles, such as the Dehnen and Einasto models. In the present…

General Relativity and Quantum Cosmology · Physics 2026-03-31 Erdinç Ulaş Saka

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…

Astrophysics · Physics 2009-11-13 Luca Ciotti , Lucia Morganti , Tim de Zeeuw

The analytical phase-space distribution function (DF) of spherical self--consistent galaxy (or cluster) models, embedded in a dark matter halo, where both density distributions follow the Hernquist profile, with different total masses and…

Astrophysics · Physics 2009-10-28 Luca Ciotti

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…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Philip F. Hopkins , Eliot Quataert

We model the mass distributions of 40 high surface brightness spiral galaxies inside their optical radii, deriving parameters of mass models by matching the predicted velocities to observed velocity maps. We use constant mass-to-light disk…

Astrophysics · Physics 2009-11-10 Eric I. Barnes , J. A. Sellwood , Arthur Kosowsky

We derive the stellar and circumstellar parameters of the Galactic compact planetary nebula Hen 2-90 with two models: the classical constant density nebula model where the emission (especially of the forbiden lines) is formed in a sphere or…

Astrophysics · Physics 2007-05-23 Michaela Kraus
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