English
Related papers

Related papers: Action-based distribution functions for spheroidal…

200 papers

We study systematically stationary solutions to the coupled Vlasov and Poisson equations which have `self-similar' or scaling symmetry in phase space. In particular, we find analytically {\it all} spherically symmetric distribution…

Astrophysics · Physics 2015-06-24 R. N. Henriksen , Lawrence M. Widrow

We describe methods for setting up self-consistent disk-bulge-halo galaxy models. The bulge and halo distribution functions (\df) are functions of $E$ and $L_z$ only. The halo's flattening and rotation can be specified. The disk \df\ is a…

Astrophysics · Physics 2016-08-30 Konrad Kuijken , John Dubinski

Cosmological models of a scalar field with dynamical equations containing fractional derivatives or derived from the Einstein-Hilbert action of fractional order, are constructed. A number of exact solutions to those equations of fractional…

General Relativity and Quantum Cosmology · Physics 2011-08-22 V. K. Shchigolev

In slowly evolving spherical potentials, $\Phi(r,t)$, radial actions are typically assumed to remain constant. Here, we construct dynamical invariants that allow us to derive the evolution of radial actions in spherical central potentials…

Astrophysics of Galaxies · Physics 2021-09-14 Jan D. Burger , Jorge Peñarrubia , Jesús Zavala

We find a numerical self-consistent stellar model by finding the distribution function of a thin disk that satisfies simultaneously the Fokker-Planck and Poisson equations. The solution of the Fokker-Planck equation is found by a direct…

Astrophysics · Physics 2009-11-11 Maximiliano Ujevic , Patricio S. Letelier

Assuming the separable augmented density, it is always possible to construct a distribution function of a spherical population with any given density and anisotropy. We consider under what conditions the distribution constructed as such is…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-19 J. An , E. Van Hese , M. Baes

We perform a theoretical analysis of the observational dependence between angular momentum of the galaxy clusters and their mass (richness), based on the method introduced in our previous paper. For that we obtain the distribution function…

Astrophysics of Galaxies · Physics 2017-12-20 V. A. Stephanovich , W. Godłowski

Reaction-diffusion models have been used over decades to study biological systems. In this context, evolution equations for probability distribution functions and the associated stochastic differential equations have nowadays become…

Statistical Mechanics · Physics 2018-10-09 C. Escudero , S. B. Yuste , E. Abad , F. Le Vot

Observed clusters should be modelled by considering the distribution function to be a random variable that quantifies the degree of excitation of the system's normal modes. A system of canonical coordinates for the space of DFs is…

Astrophysics of Galaxies · Physics 2021-08-11 Jun Yan Lau , James Binney

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 show that radiation from complex and inherently random but correlated wave sources can be modelled efficiently by using an approach based on the Wigner distribution function. Our method exploits the connection between correlation…

Chaotic Dynamics · Physics 2015-09-30 Gabriele Gradoni , Stephen Creagh , Gregor Tanner , Christopher Smartt , David Thomas

We introduce a diffusion-based generative model to describe the distribution of galaxies in our Universe directly as a collection of points in 3-D space (coordinates) optionally with associated attributes (e.g., velocities and masses),…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-24 Carolina Cuesta-Lazaro , Siddharth Mishra-Sharma

Starting from the hypothesis that the Galaxy's dark halo responded adiabatically to the infall of baryons, we have constructed a self-consistent dynamical model of the Galaxy that satisfies a large number of observations, including…

Astrophysics of Galaxies · Physics 2015-10-28 James Binney , Tilmann Piffl

We probe the feasibility of describing the structure of a multi-component axisymmetric galaxy with a dynamical model based on the Jeans equations while taking into account a third integral of motion. We demonstrate that using the third…

Astrophysics of Galaxies · Physics 2016-07-27 Rain Kipper , Peeter Tenjes , Olga Tihhonova , Antti Tamm , Elmo Tempel

Spherical models of collisionless but quasi-relaxed stellar systems have long been studied as a natural framework for the description of globular clusters. Here we consider the construction of self-consistent models under the same physical…

Astrophysics · Physics 2009-11-13 G. Bertin , A. L. Varri

We have completed a Monte-Carlo simulation to estimate the effect of binary star orbits on the measured velocity dispersion in dwarf spheroidal galaxies. This paper analyses previous attempts at this calculation, and explains the…

Astrophysics · Physics 2015-06-24 J. C. Hargreaves , G. Gilmore , J. D. Annan

A particle method for reproducing the phase space of collisionless stellar systems is described. The key idea originates in Liouville's theorem which states that the distribution function (DF) at time t can be derived from tracing necessary…

Astrophysics · Physics 2009-10-30 Shunsuke Hozumi

This paper presents a review of the fractal approach for describing the large scale distribution of galaxies. We start by presenting a brief, but general, introduction to fractals, which emphasizes their empirical side and applications…

Astrophysics · Physics 2022-05-10 Marcelo B. Ribeiro , Alexandre Y. Miguelote

Here, we model the effect of non-uniform dynamical mass distributions and their associated gravitational fields on the stationary galactic superwind solution. We do this by considering an analogue injection of mass and energy from stellar…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-04 G. A. Añorve-Zeferino , M. G. Corona-Galindo

We show different expressions of distribution functions (DFs) which depend only on the two classical integrals of the energy and the magnitude of the angular momentum with respect to the axis of symmetry for stellar systems with known…

Astrophysics · Physics 2009-06-25 Zhenglu Jiang , Leonid Ossipkov