Results 1 to 10 of about 454,773 (69)
Unstable Cold Dark Matter and the Cuspy Halo Problem in Dwarf Galaxies [PDF]
Astrophys.J.591:L107-L110,2003, 2003 We speculate that the dark halos of dwarf galaxies and low surface brightness galaxies soften their central cusps by the decay of a fraction of cold dark matter (CDM) particles to a stable particle with a recoiling velocity of a few tens km s$^{-1}$, after they have driven the formation of galactic halos.
F. J. Snchez-Salcedo
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Unitarity Bounds and the Cuspy Halo Problem [PDF]
Phys.Rev.Lett. 86 (2001) 3467-3470, 2001 Conventional Cold Dark Matter cosmological models predict small scale structures, such as cuspy halos, which are in apparent conflict with observations. Several alternative scenarios based on modifying fundamental properties of the dark matter have been proposed.
Lam Hui
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Incorporating baryon-driven contraction of dark matter halos in rotation curve fits [PDF]
A&A 665, A143 (2022), 2022 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 predicted by DM-only simulations for the baryon distributions observed in the galaxies of the SPARC database. We find that
arxiv +1 more source
How black holes turn cusps into cores [PDF]
Astrophys.Space Sci. 284 (2003) 561-564, 2002 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 cuspy NFW profiles for the density distribution in dark matter halos.
arxiv +1 more source
Mimetic Gravity: A Review of Recent Developments and Applications to Cosmology and Astrophysics
Advances in High Energy Physics, Volume 2017, Issue 1, 2017., 2017 Mimetic gravity is a Weyl‐symmetric extension of General Relativity, related to the latter by a singular disformal transformation, wherein the appearance of a dust‐like perfect fluid can mimic cold dark matter at a cosmological level. Within this framework, it is possible to provide a unified geometrical explanation for dark matter, the late‐time ...
Lorenzo Sebastiani +3 more
wiley +1 more source
Bose‐Einstein Condensate Dark Matter Halos Confronted with Galactic Rotation Curves
Advances in High Energy Physics, Volume 2017, Issue 1, 2017., 2017 We present a comparative confrontation of both the Bose‐Einstein Condensate (BEC) and the Navarro‐Frenk‐White (NFW) dark halo models with galactic rotation curves. We employ 6 High Surface Brightness (HSB), 6 Low Surface Brightness (LSB), and 7 dwarf galaxies with rotation curves falling into two classes.
M. Dwornik +4 more
wiley +1 more source
Dark Atoms and the Positron‐Annihilation‐Line Excess in the Galactic Bulge
Advances in High Energy Physics, Volume 2014, Issue 1, 2014., 2014 It was recently proposed that stable particles of charge −2, O−−, can exist and constitute dark matter after they bind with primordial helium in O‐helium (OHe) atoms. We study here in detail the possibility that this model provides an explanation for the excess of gamma radiation in the positron‐annihilation line from the galactic bulge observed by ...
J.-R. Cudell +3 more
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A Limit on the Cosmological Mass Density and Power Spectrum from the Rotation Curves of Low Surface Brightness Galaxies [PDF]
Astrophys.J. 584 (2003) 566-576, 2002 The concentrations of the cuspy dark matter halos predicted by simulations of cold dark matter are related to the cosmology in which the halos form. Observational constraints on halo concentration therefore map into constraints on cosmological parameters.
arxiv +1 more source
A cuspy dark matter halo [PDF]
, 2021 The cusp-core problem is one of the main challenges of the cold dark matter paradigm on small scales: the density of a dark matter halo is predicted to rise rapidly toward the center as rho ~ r^alpha with alpha between -1 and -1.5, while such a cuspy profile has not been clearly observed.
arxiv +1 more source
The Mitchell Spectrograph: Studying Nearby Galaxies with the VIRUS Prototype
Advances in Astronomy, Volume 2013, Issue 1, 2013., 2013 The Mitchell Spectrograph (a.k.a. VIRUS‐P) on the 2.7 m Harlan J. Smith telescope at McDonald Observatory is currently the largest field of view (FOV) integral field unit (IFU) spectrograph in the world (1.7′ × 1.7′). It was designed as a prototype for the highly replicable VIRUS spectrograph which consists of a mosaic of IFUs spread over a 16 ...
Guillermo A. Blanc +1 more
wiley +1 more source