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相关论文: Dwarf Galaxy Sized Monopoles as Dark Matter?

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The Milky Way (MW) dwarf spheroidal (dSph) satellites are known to be the most dark-matter (DM) dominated galaxies with estimates of dark to baryonic matter reaching even above one hundred. It comes from the assumption that dwarfs are…

Dwarf spheroidal galaxies are the most common type of galaxies, and are the most dark matter dominated objects in the Universe. Therefore, they are ideal laboratories to test any dark matter model. The Bose-Einstein condensate/scalar field…

星系天体物理 · 物理学 2015-07-29 V. Lora

We present Halpha rotation curves for a sample of 15 dwarf and LSB galaxies. From these, we derive limits on the slopes of the central mass distributions. Assuming the density distributions of dark matter halos follow a power-law at small…

天体物理学 · 物理学 2008-11-26 R. A. Swaters , B. F. Madore , F. C. van den Bosch , M. Balcells

We study properties of dark matter halos at high redshifts z=2-10 for a vast range of masses with the emphasis on dwarf halos with masses 10^7-10^9 Msun/h. We find that the density profiles of relaxed dwarf halos are well fitted by the NFW…

天体物理学 · 物理学 2009-11-10 P. Colin , A. Klypin , O. Valenzuela , S. Gottlober

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…

天体物理学 · 物理学 2009-11-07 M. I. Wilkinson , J. Kleyna , N. W. Evans , G. Gilmore

The standard cold dark matter (CDM) model has recently been challenged by the claim that dwarf galaxies have dark matter halos with constant density cores. Consequently, numerous alternative dark matter candidates have recently been…

天体物理学 · 物理学 2008-11-26 Frank C. van den Bosch , Rob A. Swaters

We investigate the nature of the newly discovered Ultra Faint dwarf spheroidal galaxies (UF dSphs) in a general cosmological context simultaneously accounting for various ``classical`` dSphs and Milky Way properties including their…

天体物理学 · 物理学 2009-11-13 Stefania Salvadori , Andrea Ferrara

The cold dark matter (CDM) model has two unsolved issues: simulations overpredict the satellite abundance around the Milky Way (MW) and it disagrees with observations of the central densities of dwarf galaxies which prefer constant density…

星系天体物理 · 物理学 2015-09-10 Victor H. Robles , V. Lora , T. Matos , F. J. Sanchez-Salcedo

Dark matter is thought to make up most of the matter density of the Universe, yet its true nature remains uncertain. Among dark matter theories, Weakly Interacting Massive Particles (WIMPs) are a prominent candidate for dark matter because…

高能天体物理现象 · 物理学 2023-09-20 Micael Andrade , Aion Viana

Recent studies found the densities of dark matter (DM) subhaloes which surround nearby dwarf spheroidal galaxies (dSphs) to be significantly lower than those of the most massive subhaloes expected around Milky Way sized galaxies in…

星系天体物理 · 物理学 2015-06-22 Go Ogiya , Andreas Burkert

Due to a large mass-to-light ratio and low astrophysical backgrounds, dwarf spheroidal galaxies (dSphs) are considered to be one of the most promising targets for dark matter searches via gamma rays. The Fermi LAT Collaboration has recently…

高能天体物理现象 · 物理学 2019-08-13 Alex Drlica-Wagner

Dark matter (DM) halos of Sc-Im and dwarf spheroidal (dSph) galaxies satisfy scaling laws: halos in lower-luminosity galaxies have smaller core radii, higher central densities, and smaller velocity dispersions. These results are based on…

星系天体物理 · 物理学 2016-02-17 John Kormendy , K. C. Freeman

We investigate structural properties of dark matter halos of disk galaxies in LCDM cosmology, using a well-defined sample of 81 disk-dominated galaxies from the SDSS redshift survey. We model the mass-velocity and fundamental plane…

天体物理学 · 物理学 2009-11-11 Oleg Y. Gnedin , David H. Weinberg , James Pizagno , Francisco Prada , Hans-Walter Rix

Small-scale structure is studied in the context of dissipative dark matter, arising for instance in models with a hidden unbroken Abelian sector, so that dark matter couples to a massless dark photon. The dark sector interacts with ordinary…

宇宙学与河外天体物理 · 物理学 2018-12-13 Robert Foot , Sunny Vagnozzi

Dwarf spheroidal (dSph) galaxies are considered the basic building blocks of the galaxy formation process in the LCDM (Lambda Cold Dark Matter) hierarchical cosmological model. These galaxies are believed to be the most dark matter (DM)…

星系天体物理 · 物理学 2015-06-16 P. Assmann , M. Fellhauer , M. I. Wilkinson , R. Smith , M. Blaña

We reconsider the lower bound on the mass of a fermionic dark matter (DM) candidate resulting from the existence of known small Dwarf Spheroidal galaxies, in the hypothesis that their DM halo is constituted by degenerate fermions, with…

星系天体物理 · 物理学 2018-03-28 Chiara Di Paolo , Fabrizio Nesti , Francesco L. Villante

The demographics of dwarf galaxy populations have long been in tension with predictions from the Cold Dark Matter (CDM) paradigm. If primordial density fluctuations were scale-free as predicted, dwarf galaxies should themselves host dark…

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…

天体物理学 · 物理学 2011-08-23 F. J. Sanchez-Salcedo

We investigate the nature of Ultra Faint dwarf spheroidal galaxies (UF dSphs) in a general cosmological context, simultaneously accounting for various "classical" dSphs and Milky Way (MW) properties, including their Metallicity Distribution…

宇宙学与河外天体物理 · 物理学 2015-05-19 Stefania Salvadori , Andrea Ferrara

The stellar-mass--halo-mass (SMHM) relation is central to our understanding of galaxy formation and the nature of dark matter. However, its normalisation, slope, and scatter are highly uncertain at dwarf galaxy scales. In this paper, we…