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Related papers: Cores and Cusps in the Dwarf Spheroidals

200 papers

The inner profile of Dark Matter (DM) halos remains one of the central problems in small-scale cosmology. At present, the problem can not be resolved in dwarf spheroidal galaxies due to a degeneracy between the DM profile and the velocity…

Astrophysics of Galaxies · Physics 2014-03-19 Thomas Richardson , Douglas Spolyar , Matt Lehnert

The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measurement of line-of-sight velocities for resolved stars, which…

The condensation of baryons within a dark matter (DM) halo during galaxy formation should result in some contraction of the halo as the combined system settles into equilibrium. We quantify this effect on the cuspy primordial halos…

Astrophysics of Galaxies · Physics 2022-09-21 Pengfei Li , Stacy S. McGaugh , Federico Lelli , James M. Schombert , Marcel S. Pawlowski

We present a synthesis of recent photometric and kinematic data for several of the most dark-matter dominated galaxies. There is a bimodal distribution in half-light radii, with stable star clusters always being smaller than $\sim30$pc,…

The free streaming of warm dark matter particles dampens the fluctuation spectrum, flattens the mass function of haloes and imprints a fine grained phase density limit for dark matter structures. The phase space density limit is expected to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Andrea V. Maccio' , Sinziana Paduroiu , Donnino Anderhalden , Aurel Schneider , Ben Moore

By fitting a flexible stellar anisotropy model to the observed surface brightness and line-of-sight velocity dispersion profiles of Draco we derive a sequence of cosmologically plausible two-component (stars + dark matter) models for this…

Astrophysics · Physics 2009-11-13 Sergey Mashchenko , Alison Sills , H. M. P. Couchman

According to the current concordance cosmological model, the dark matter (DM) particles are collision-less and produce self-gravitating structures with a central cusp which, generally, is not observed. The observed density tends to a…

Astrophysics of Galaxies · Physics 2023-07-06 Jorge Sanchez Almeida , Angel R. Plastino , Ignacio Trujillo

We use N-body simulations to revisit the globular cluster (GC) ``timing problem'' in the Fornax dwarf spheroidal (dSph). In agreement with earlier work, we find that, due to dynamical friction, GCs sink to the center of dark matter halos…

Astrophysics of Galaxies · Physics 2020-01-08 Noah Meadows , Julio F. Navarro , Isabel Santos-Santos , Alejandro Benitez-Llambay , Carlos Frenk

Simulations have established that each halo of collisionless dark matter is expected to contain a $\rho = A r^{-1.5}$ density cusp at its center. This prompt cusp is a relic of the halo's earliest moments and has a mass comparable to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-29 M. Sten Delos

It is shown that, if the tracer population is supported by a spherical dark halo with a core or a cusp diverging more slowly than that of a singular isothermal sphere, the logarithmic cusp slope 'g' of the tracers must be given exactly by…

Astrophysics of Galaxies · Physics 2011-02-11 Jin H. An , N. Wyn Evans

In the past years a wealth of observations allowed to unravel the structural properties of the Dark Matter Halos around spirals. First, their rotation curves follow an Universal profile (URC) that can be described in terms of an exponential…

Astrophysics · Physics 2016-08-30 Paolo Salucci

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

The results obtained from a study of the mass distribution of 36 spiral galaxies are presented. The galaxies were observed using Fabry-Perot interferometry as part of the GHASP survey. The main aim of obtaining high resolution H alpha 2D…

Astrophysics · Physics 2009-11-13 M. Spano , M. Marcelin , P. Amram , C. Carignan , B. Epinat , O. Hernandez

We forecast parameter uncertainties on the mass profile of a typical Milky Way dwarf spheroidal (dSph) galaxy using the spherical Jeans Equation and Fisher matrix formalism. We show that radial velocity measurements for 1000 individual…

Astrophysics of Galaxies · Physics 2021-12-13 Juan Guerra , Marla Geha , Louis E. Strigari

Motivated by the observation of extended stellar cores in dark matter (DM) dominated dwarf galaxies, this study investigates a simple mechanism by which stellar cores can form as a result of DM halo expansion. Several non-CDM models predict…

Astrophysics of Galaxies · Physics 2025-10-22 Jorge Sanchez Almeida , Angel R. Plastino , Ignacio Trujillo

The dynamical friction timescale of massive globular clusters (GCs) in the inner regions of cuspy dark haloes in dwarf spheroidal (dSph) galaxies can be much shorter than the Hubble time. This implies that a small fraction of the GCs is…

Astrophysics of Galaxies · Physics 2022-02-09 F. J. Sanchez-Salcedo , V. Lora

The cold dark matter model predicts cuspy dark matter halos. However, it has been found that, in some low-mass galaxies, cored dark halos provide a better description of their internal dynamics. Here we give constraints on the dark halo…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 V. Lora , E. K. Grebel , F. J. Sanchez-Salcedo , A. Just

Within the framework of the cold dark matter (CDM) cosmogony, a central cusp in the density profiles of virialized dark haloes is predicted. This prediction disagrees with the soft inner halo mass distribution inferred from observations of…

Astrophysics · Physics 2009-10-31 C. Firmani , E. D'Onghia , V. Avila-Reese , G. Chincarini , X. Hernandez

The existence of two kinematically and chemically distinct stellar subpopulations in the Sculptor and Fornax dwarf galaxies offers the opportunity to constrain the density profile of their matter haloes by measuring the mass contained…

The evolution of halos consisting of weakly self-interacting dark matter particles is summarized. The halos initially contain a central density cusp as predicted by cosmological models. Weak self-interaction leads to the formation of an…

Astrophysics · Physics 2007-05-23 Andreas Burkert