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We provide prescriptions to evaluate the dynamical mass ($M_{\rm dyn}$) of galaxies from kinematic measurements of stars or gas using analytic considerations and the VELA suite of cosmological zoom-in simulations at $z=1-5$. We find that…

Astrophysics of Galaxies · Physics 2021-07-07 Michael Kretschmer , Avishai Dekel , Jonathan Freundlich , Sharon Lapiner , Daniel Ceverino , Joel Primack

Jeans instability is analysed in an expanding universe within the framework of BGK model of the Boltzmann equation and Poisson equations. The background is characterized by a comoving Maxwellian distribution function and a space-time…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Gilberto M. Kremer

The so-called ``symplectic method'' is used for studying the linear stability of a self-gravitating collisionless stellar system, in which the particles are also submitted to an external potential. The system is steady and spherically…

Astrophysics · Physics 2015-06-24 J. Perez , J-J Aly

Corda, Mosquera Cuesta and Lorduy Gomez have shown that spherically symmetric stationary states can be used as a model for galaxies in the framework of the linearized R^2 gravity. Those states could represent a partial solution to the Dark…

General Relativity and Quantum Cosmology · Physics 2016-10-17 Rishabh Jain , Burra G. Sidharth , Christian Corda

To learn about basic aspects of nano-scale spherical molecular shells during their formation, spherically curved two-dimensional N-particle Lennard-Jones systems are simulated, studying curvature evolution paths at zero-temperature. For…

Atomic and Molecular Clusters · Physics 2009-11-11 J. M. Voogd , P. M. A. Sloot , R. van Dantzig

The Jeans analysis is often used to infer the total density of a system by relating the velocity moments of an observable tracer population to the underlying gravitational potential. This technique has recently been applied in the search…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-21 Thomas Richardson , Malcolm Fairbairn

The dynamics of self-gravitating fluids is analyzed within the framework of a collisionless Boltzmann equation in the presence of gravitational fields and Poisson equation. Two cases are analyzed: a system with baryonic and dark matter in a…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-06 Gilberto M. Kremer

The post-Newtonian Jeans equation for stationary self-gravitating systems is derived from the post-Newtonian Boltzmann equation in spherical coordinates. The Jeans equation is coupled with the three Poisson equations from the post-Newtonian…

General Relativity and Quantum Cosmology · Physics 2022-03-15 Gilberto M. Kremer

The time evolution of initially balanced, rapidly rotating models for an isolated disk of highly flattened galaxies of stars is calculated. The method of direct integration of the Newtonian equations of motion of stars over a time span of…

Astrophysics · Physics 2007-05-23 Evgeny Griv , Michael Gedalin , Edward Liverts , David Eichler , Yehoshua Kimhi , Chi Yuan

I present a flexible solution for the axisymmetric Jeans equations of stellar hydrodynamics under the assumption of an anisotropic (three-integral) velocity ellipsoid aligned with the spherical polar coordinate system. I describe and test a…

Astrophysics of Galaxies · Physics 2020-04-24 Michele Cappellari

The kinematics of stars in dwarf spheroidal galaxies have been studied to understand the structure of dark matter halos. However, the kinematic information of these stars is often limited to celestial positions and line-of-sight velocities,…

Astrophysics of Galaxies · Physics 2025-06-03 Sung Hak Lim , Kohei Hayashi , Shun'ichi Horigome , Shigeki Matsumoto , Mihoko M. Nojiri

We present the theoretical framework to efficiently solve the Jeans equations for multi-component axisymmetric stellar systems, focusing on the scaling of all quantities entering them. The models may include an arbitrary number of stellar…

Astrophysics of Galaxies · Physics 2021-06-30 C. Caravita , L. Ciotti , S. Pellegrini

Axisymmetric Jeans modelling is widely used to infer galaxy mass profiles from integral-field kinematics, but existing implementations maintain tractability by adopting highly restricted anisotropy prescriptions. I present a new spectral…

Astrophysics of Galaxies · Physics 2026-03-03 Michele Cappellari

The Jeans criterion is one cornerstone in our understanding of gravitational fragmentation. A critical limitation of the Jeans criterion is that the background density is assumed to be a constant, which is often not true in dynamic…

Astrophysics of Galaxies · Physics 2024-01-30 Guang-Xing Li

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

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

Dynamics and collapse of collisionless self-gravitating systems is described by the coupled collisionless Boltzmann and Poisson equations derived from $f(R)$-gravity in the weak field approximation. Specifically, we describe a system at…

General Relativity and Quantum Cosmology · Physics 2015-06-03 S. Capozziello , M. De Laurentis , I. De Martino , M. Formisano , S. D. Odintsov

This is an addendum to the paper by Cappellari (2008, MNRAS, 390, 71), which presented a simple and efficient method to model the stellar kinematics of axisymmetric stellar systems. The technique reproduces well the integral-field…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-30 Michele Cappellari

The one-dimensional symmetric exclusion process, the simplest interacting particle process, is a lattice-gas made of particles that hop symmetrically on a discrete line respecting hard-core exclusion. The system is prepared on the infinite…

Statistical Mechanics · Physics 2017-04-26 T. Imamura , K. Mallick , T. Sasamoto

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. We focus on the case of spherical systems, which are…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-20 Amr El-Zant