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Related papers: Orbit-based dynamical models of the Sculptor dSph …

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We present predictions for the line-of-sight velocity dispersion profiles of dwarf spheroidal galaxies and compare them to observations in the case of the Fornax dwarf. The predictions are made in the framework of standard dynamical theory…

Astrophysics · Physics 2009-11-06 Ewa L. Lokas

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 apply four different mass modelling methods to a suite of publicly available mock data for spherical stellar systems. We focus on the recovery of the density and velocity anisotropy as a function of radius, using either line-of-sight…

Astrophysics of Galaxies · Physics 2020-12-02 J. I. Read , G. A. Mamon , E. Vasiliev , L. L. Watkins , M. G. Walker , J. Penarrubia , M. Wilkinson , W. Dehnen , P. Das

It has been suggested that the internal dynamics of dwarf spheroidal galaxies (dSphs) can be used to test whether or not ultralight axions with $m_a\sim 10^{-22}\text{eV}$ are a preferred dark matter candidate. However, comparisons to…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-22 Alma X. Gonzalez-Morales , David J. E. Marsh , Jorge Peñarrubia , L. Arturo Ureña-López

We consider the problem of determining the structure of the dark halo of nearby dwarf spheroidal galaxies (dSphs) from the spherical Jeans equations. Whether the dark halos are cusped or cored at the centre is an important strategic problem…

Astrophysics · Physics 2009-11-13 N. W. Evans , J. An , M. G. Walker

We study the density profile of a dwarf halo in the decaying dark matter (DDM) cosmology, using a new algorithm that resolves halo density profiles down to the innermost $700$ pc robustly with high efficiency. Following Schwarzschild's…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-20 Jianxiong Chen , M. -C. Chu

We build a spherical halo model for galaxies using a general scalar-tensor theory of gravity in its Newtonian limit. The scalar field is described by a time-independent Klein-Gordon equation with a source that is coupled to the standard…

Astrophysics of Galaxies · Physics 2009-03-24 Jorge L. Cervantes-Cota , Mario A. Rodriguez-Meza , Dario Nunez

We construct the Schwarzschild dynamical models for 11 early-type galaxies with the SAURON and Mitchell stellar IFUs out to $2-4 R_\mathrm{e}$, and construct dynamical models with combined stellar and HI kinematics for a subsample of 4…

Astrophysics of Galaxies · Physics 2024-02-01 Meng Yang , Ling Zhu , Yu Lei , Nicholas Boardman , Anne-Marie Weijman , Raffaella Morganti , Tom Oosterloo , Pierre-Alain Duc

An analytic galaxy model with $\rho \sim r^{-1}$ at small radii and $\rho \sim r^{-3.5}$ at large radii is presented. The asymptotic density fall-off is slower than the Hernquist model, but faster than the Navarro-Frenk-White (NFW) profile…

Astrophysics of Galaxies · Physics 2018-02-21 E. Lilley , N. W. Evans , J. L. Sanders

Using N-body simulations we study the phenomenon of radial orbit instability occurring in dark matter haloes of the size of a dwarf galaxy. We carried out simulations of seven spherical models, with the same standard NFW density profile but…

Astrophysics of Galaxies · Physics 2016-10-21 Grzegorz Gajda , Ewa L. Lokas , Radoslaw Wojtak

We present new dynamical models of dwarf spheroidal galaxies (dSphs) in which both the stellar component and the dark halo are described by analytic distribution functions that depend on the action integrals. In their most general form…

Astrophysics of Galaxies · Physics 2018-08-01 Raffaele Pascale , Lorenzo Posti , Carlo Nipoti , James Binney

(Abridged) We use N-body simulations to study the evolution of dwarf spheroidal galaxies (dSphs) driven by galactic tides. We adopt a cosmologically-motivated model where dSphs are approximated by a King model embedded within an NFW halo.…

Astrophysics · Physics 2009-11-13 Jorge Penarrubia , Julio F. Navarro , Alan W. McConnachie

It is now established that several of the Local Group dwarf Spheroidal galaxies (dSphs) have large mass-to-light ratios. We consider the possibility that the dark matter in the halos of dSphs is composed of massive black holes with masses…

Astrophysics · Physics 2009-11-10 Shoko Jin , Jeremiah P. Ostriker , Mark I. Wilkinson

We have performed the first detailed simulation of the horizontal branch of the Sculptor dwarf spheroidal galaxy by means of synthetic modelling techniques,taking consistently into account the star formation history and metallicity…

Astrophysics of Galaxies · Physics 2015-06-17 Maurizio Salaris , Thomas de Boer , Eline Tolstoy , Giuliana Fiorentino , Santi Cassisi

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 investigate the mass profile of LambdaCDM halos using a suite of numerical simulations spanning five decades in halo mass, from dwarf galaxies to rich galaxy clusters. Our analysis confirms the proposal of Navarro, Frenk & White (NFW)…

Following a number of conflicting studies of M87's mass profile, we undertake a dynamical analysis of multiple tracer populations to constrain its mass over a large radius range. We combine stellar kinematics in the central regions with the…

Astrophysics of Galaxies · Physics 2016-01-27 L. J. Oldham , M. W. Auger

We present a new family of spherically symmetric models for the luminous components of elliptical and spiral galaxies and their dark matter haloes. Our starting point is a general expression for the logarithmic slope $\alpha(r) =…

Astrophysics · Physics 2009-11-10 V. F. Cardone , E. Piedipalumbo , C. Tortora

Dark matter (DM) halos formed in CDM cosmologies seem to be characterized by a power law phase-space density profile. The density of the DM halos is often fitted by the NFW profile but a better fit is provided by the Sersic fitting formula.…

Astrophysics · Physics 2009-11-13 Amir Zait , Yehuda Hoffman , Isaac Shlosman

It has been shown in previous work that DARKexp, which is a theoretically derived, maximum entropy, one shape parameter model for isotropic collisionless systems, provides very good fits to simulated and observed dark-matter halos.…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-20 Liliya L. R. Williams , Jens Hjorth , Radoslaw Wojtak