Results 11 to 20 of about 31,858 (173)
Inflation and the dwarf galaxy problem [PDF]
Physical Review D, 2000 Cosmological N-body simulations with scale-invariant initial perturbations show too many virialized objects of dwarf-galaxy masses in a typical galactic halo in contradiction to observation and stability of galactic discs. We present a model of double hybrid inflation which predicts density fluctuations with a small-scale cutoff to account for the ...
Jun’ichi Yokoyama
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The Cusp–Core Problem in Gas-Poor Dwarf Spheroidal Galaxies [PDF]
Galaxies, 2021 This review deals with the inconsistency of inner dark matter density profiles in dwarf galaxies, known as the cusp–core problem. In particular, we aim to focus on gas-poor dwarf galaxies. One of the most promising solutions to this cold dark matter small-scale issue is the stellar feedback, but it seems to be only designed for gas-rich dwarfs. However,
Pierre Boldrini
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Missing Dwarf Problem in Galaxy Clusters [PDF]
Publications of the Astronomical Society of Japan, 2007 Abstract We investigated the formation and evolution of CDM subhalos in galaxy-sized and cluster-sized halos by means of $N$-body simulations. Our aim was to make clear what the “dwarf galaxy problem” is. It has been argued that the number of subhalos in simulated galaxy-sized halos is too large compared with the observed number of ...
Hiroyuki Kase +2 more
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Formation of dwarf galaxies and small-scale problems of CDM [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractThe concordance cosmological model based on cold dark matter makes definitive predictions for the growth of galaxies in the Universe, which are being actively studied using numerical simulations. These predictions appear to contradict the observations of dwarf galaxies.
Oleg Y. Gnedin
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The G Dwarf Problem Exists in Other Galaxies [PDF]
The Astronomical Journal, 1996 14 pages, LaTeX includes 3 postscript figures. Uses AAS LaTeX v 4.0 and times.sty. Accepted for publication in the Astronomical Journal.
Guy Worthey, Ben Dorman, Lewis A. Jones
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An Internal Second-Parameter Problem in the Sculptor Dwarf Spheroidal Galaxy [PDF]
The Astrophysical Journal, 1999 15 pages, 4 figures, LaTeX, uses aastex.
Steven R. Majewski +3 more
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The G-dwarf problem in the Galaxy [PDF]
New Astronomy, 2007 The empirical differential metallicity distribution (EDMD) is deduced for (i) local thick disk stars; (ii) likely metal-weak thick disk stars; (iii) chemically selected local G dwarfs, with the corrections performed in order to take into account the stellar scale height; in addition to previous results related to (iv) solar neighbourhood halo subdwarfs;
R. Caimmi
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Is there a dwarf galaxy satellite-of-satellite problem in $Λ$CDM? [PDF]
Astronomy & Astrophysics, 2023 Dark matter clusters on all scales, and it is therefore expected that even substructure should host its own substructure. Using the Extragalactic Distance Database, we searched for dwarf-galaxy satellites of dwarf galaxies, that is, satellite-of-satellite galaxies, corresponding to these substructures of substructure. From investigation of Hubble Space
Oliver Müller +4 more
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Unstable Cold Dark Matter and the Cuspy Halo Problem in Dwarf Galaxies [PDF]
The Astrophysical Journal, 2003 5 pages, 1 figure, accepted for publication in ...
F. J. Snchez-Salcedo
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A New Culprit in the Second-Parameter Problem in the Sculptor Dwarf Spheroidal Galaxy? [PDF]
The Astrophysical Journal, 1999 Color-magnitude diagrams from deep, wide-field CCD photometry of the Sculptor dwarf spheroidal galaxy reveal that the red horizonal branch (RHB) stars are strongly concentrated towards the center of the galaxy relative to the dominant old population in Sculptor, confirming an earlier claim of such a gradient (Da Costa et al. 1996).
Denise Hurley‐Keller +2 more
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