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Related papers: Cored density profiles in the DARKexp model

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Dwarf galaxies are observed to have linearly rising rotation curves, which indicate constant density cores in their centers. These do not arise naturally from dark matter only simulations, giving rise to the ``core-cusp'' problem.…

Astrophysics of Galaxies · Physics 2025-08-20 Liliya L. R. Williams , Jens Hjorth , Evan D. Skillman

In the DARKexp framework for collisionless isotropic relaxation of self--gravitating matter, the central object is the differential energy distribution $n(E)$, which takes a maximum--entropy form proportional to $\exp[-\beta(E - \Phi(0))] -…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-23 Claudio Destri

We investigate constraints on the inner stellar density profile from photometric data of dwarf spheroidal and ultra-faint dwarf galaxies. Our aim is to clarify under what conditions cored stellar profiles require dark matter halos that are…

Dark-matter halos grown in cosmological simulations appear to have central NFW-like density cusps with mean values of $d\log\rho/d\log r \approx -1$, and some dispersion, which is generally parametrized by the varying index $\alpha$ in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-15 Jens Hjorth , Liliya L. R. Williams , Radosław Wojtak , Michael McLaughlin

Using the formalism of the spherical infall model the structure of collapsed and virialized dark halos is calculated for a variety of scale-free initial conditions. In spite of the scale-free cosmological nature of the problem, the collapse…

Astrophysics · Physics 2009-10-31 Ewa L. Lokas , Yehuda Hoffman

The observed rotation curves of low surface brightness (LSB) galaxies play an essential role in studying dark matter, and indicate that there exists a central constant density dark matter core. However, the cosmological N-body simulations…

Astrophysics of Galaxies · Physics 2021-07-02 Xiaobo Gong , Meirong Tang , Zhaoyi Xu

We present an equilibrium statistical mechanical theory of collisionless self-gravitational systems with isotropic velocity distributions. Compared to existing standard theories, we introduce two changes: (1) the number of possible…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-05 Jens Hjorth , Liliya L. R. Williams

The shapes of individual self-gravitating structures of an ensemble of identical, collisionless particles have remained elusive for decades. In particular, a reason why mass density profiles like the Navarro-Frenk-White or the Einasto…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner

The distribution of dark matter in the inner regions of galaxies poses a key challenge for small-scale {\Lambda}CDM cosmology. While cold dark matter simulations predict cuspy inner density profiles, observations of low surface brightness…

Astrophysics of Galaxies · Physics 2026-02-09 Sougata Sarkar , Prerana Biswas , Veselina Kalinova , Nirupam Roy , Narendra Nath Patra , Sushma Kurapati

Rotation curves of galaxies probe their total mass distributions, including dark matter. Dwarf galaxies are excellent systems to investigate the dark matter density distribution, as they tend to have larger fractions of dark matter compared…

This review aims at proposing to the field an overview of the Cusp-core problem, including a discussion of its advocated solutions, assessing how each can satisfactorily provide a description of central densities. Whether the Cusp-core…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-29 Antonino Del Popolo , Morgan Le Delliou

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 role of systematic effects in observational studies of the cusp-core problem under the minimum disc approximation using a suite of high-resolution (25-pc softening length) hydrodynamical simulations of dwarf galaxies. We mimic…

Astrophysics of Galaxies · Physics 2016-12-19 Juan C. B. Pineda , Christopher C. Hayward , Volker Springel , Claudia Mendes de Oliveira

We propose and successfully test against new cosmological simulations a novel analytical description of the physical processes associated with the origin of cored dark matter density profiles. In the simulations, the potential in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Andrew Pontzen , Fabio Governato

It is shown that the cuspy density distributions observed in the cores of elliptical galaxies can be realized by dissipationless gravitational collapse. The initial models consist of power-law density spheres such as $\rho\propto r^{-1}$…

Astrophysics · Physics 2009-10-31 S. Hozumi , A. Burkert , T. Fujiwara

The core-cusp problem is one of the controversial issues in the standard paradigm of $\Lambda$ cold dark matter ($\Lambda$CDM) theory. However, under the assumption of conventional spherical symmetry, the strong degeneracy among model…

Astrophysics of Galaxies · Physics 2020-12-02 Kohei Hayashi , Masashi Chiba , Tomoaki Ishiyama

In this paper, we present the density, \rho, velocity dispersion, \sigma, and \rho/\sigma^3 profiles of isotropic systems which have the energy distribution, N(E)\propto[\exp(\phi_0-E)-1], derived in Paper I. This distribution, dubbed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Liliya L. R. Williams , Jens Hjorth

Collapsing collisionless particle systems form gravitational bound halos with cuspy density profiles. Also hierarchical merging of these systems produce remnants with cuspy central density profiles. These results lead to the assumption of…

Astrophysics · Physics 2009-11-07 Marc Hemsendorf

An analytical solution for the discrepancy between observed core-like profiles and predicted cusp profiles in dark matter halos is studied. We calculate the distribution function for Navarro-Frenk-White halos and extract energy from the…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-27 Rafael S. de Souza , Emille E. O. Ishida

Context. The cusp-core discrepancy is one of the major problems in astrophysics. It results from comparing the observed mass distribution of galaxies with the predictions of Cold Dark Matter simulations. The latter predict a cuspy density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. van Eymeren , C. Trachternach , B. S. Koribalski , R. -J. Dettmar
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