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Related papers: Self-consistent triaxial models

200 papers

Following earlier authors, we re-examine constraints on the radial velocity anisotropy of generic stellar systems using arguments for phase space density positivity, stability, and separability. It is known that although the majority of…

Astrophysics of Galaxies · Physics 2015-06-19 Jeremy A. Barber , Hongsheng Zhao

We assemble a statistical set of global mass models for ~2,000 nearly spherical SDSS galaxies at a mean redshift of 0.12 based on their aperture velocity dispersions and newly derived luminosity profiles in conjunction with published…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Kyu-Hyun Chae , Mariangela Bernardi , Andrey V. Kravtsov

We present a new model for galactic bars with exponentially falling major axis luminosity profiles and Gaussian cross-sections. This is based on the linear superposition of Gaussian potential-density pairs with an exponential weight…

Astrophysics of Galaxies · Physics 2020-02-26 D. P. McGough , N. W. Evans , J. L. Sanders

We introduce a very simple model of a dark halo. It is a close relative of Hernquist's model, being generated by the same transformation but this time applied to the logarithmic potential rather than the point mass. The density is…

Astrophysics of Galaxies · Physics 2015-06-22 N. W. Evans , A. A. Williams

In this paper, we have studied gravitational collapse and expansion of non-static anisotropic fluid in $5D$ Einstein Gauss-Bonnet gravity. For this purpose, the field equations have been modeled and evaluated for the given source and…

General Relativity and Quantum Cosmology · Physics 2018-12-19 G. Abbas , M. Tahir

We use Laskar's frequency mapping technique to study the dynamics of triaxial galaxies with central density cusps and nuclear black holes. For ensembles of 10^4 orbits, we numerically compute the three fundamental frequencies of the motion,…

Astrophysics · Physics 2009-10-30 Monica Valluri , David Merritt

Similarity solutions play an important role in many fields of science: we consider here similarity in stochastic dynamics. Important issues are not only the existence of stochastic similarity, but also whether a similarity solution is…

Dynamical Systems · Mathematics 2011-11-08 Wei Wang , A. J. Roberts

We use analytical and N-body methods to examine the survival of wide stellar binaries against repeated encounters with dark substructures orbiting in the dark matter haloes of dwarf spheroidal galaxies (dSphs). Our models adopt…

Astrophysics of Galaxies · Physics 2010-06-01 Jorge Penarrubia , Sergey E. Koposov , Matthew G. Walker , Gerry Gilmore , N. Wyn Evans , Craig D. Mackay

The stellar velocity fields of elliptical galaxies hold clues to their dynamical structure and origin. The construction of velocity field models is greatly simplified by assuming an approximate geometrical form for the streamlines of the…

Astrophysics · Physics 2009-10-30 R. F. Anderson , Thomas S. Statler

We study equilibrium configurations of non-Euclidean plates, in which the reference metric is uniaxially periodic. This work is motivated by recent experiments on thin sheets of composite thermally responsive gels [1]. Such sheets bend…

Pattern Formation and Solitons · Physics 2015-06-12 Michael Moshe , Eran Sharon , Raz Kupferman

Considering galaxies as self - gravitating systems of many collisionless particles allows to use methods of statistical mechanics inferring the distribution function of these stellar systems. Actually, the long range nature of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 V. F. Cardone , M. P. Leubner , A. Del Popolo

Over the last few decades, classical density-functional theory (DFT) and its dynamic extensions (DDFTs) have become powerful tools in the study of colloidal fluids. Recently, previous DDFTs for spherically-symmetric particles have been…

Statistical Mechanics · Physics 2016-08-02 Miguel A. Durán-Olivencia , Benjamin D. Goddard , Serafim Kalliadasis

In this paper we investigate the gravothermal instability of spherical stellar systems endowed with a radially anisotropic velocity distribution. We focus our attention on the effects of anisotropy on the conditions for the onset of the…

Astrophysics · Physics 2009-10-30 M. Magliocchetti , G. Pucacco , E. Vesperini

Self-consistent chaotic transport is studied in a Hamiltonian mean-field model. The model provides a simplified description of transport in marginally stable systems including vorticity mixing in strong shear flows and electron dynamics in…

Dynamical Systems · Mathematics 2016-01-11 D. Martínez-del-Río , D. del-Castillo-Negrete , A. Olvera , R. Calleja

In spite of planetary resonances being a common dynamical mechanism acting on planetary systems, no general model exists for describing their properties, particularly for commensurabilities of any order and arbitrary values of the…

Earth and Planetary Astrophysics · Physics 2021-02-24 Tabaré Gallardo , Cristián Beaugé , Cristian A. Giuppone

$N$-body simulations have unveiled several apparently universal properties of dark matter halos, including a cusped density profile, a power-law pseudo phase-space density $\rho/\sigma_r^3$, and a linear $\beta-\gamma$ relation between the…

Astrophysics · Physics 2011-02-11 Emmanuel Van Hese , Maarten Baes , Herwig Dejonghe

We present a family of self-consistent, spherical, lowered isothermal models, consisting of one or more mass components, with parameterised prescriptions for the energy truncation and for the amount of radially biased pressure anisotropy.…

Instrumentation and Methods for Astrophysics · Physics 2016-09-20 Mark Gieles , Alice Zocchi

The density profiles of dark matter haloes are commonly described by fitting functions such as the NFW or Einasto models, but these approximations break down in the transition region where halos become dominated by newly accreting matter.…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-10 Benedikt Diemer

This paper introduces a new two-parameter family of dwarf spheroidal (dSph) galaxy models. The density distribution has a Plummer profile and falls like the inverse fourth power of distance in projection, in agreement with the star-count…

Astrophysics · Physics 2009-11-07 M. I. Wilkinson , J. Kleyna , N. W. Evans , G. Gilmore

The present-day response of a Galactic disc stellar population to a non-axisymmetric perturbation of the potential has previously been computed through perturbation theory within the phase-space coordinates of the unperturbed axisymmetric…

Astrophysics of Galaxies · Physics 2017-08-30 Giacomo Monari , Benoit Famaey , Jean-Baptiste Fouvry , James Binney