Results 1 to 10 of about 31,858 (173)

On the Dwarf Galaxy Rotation Curve Diversity Problem [PDF]

Galaxies, 2018
In this paper, we show how baryonic physics can solve the problem of the striking diversity in dwarf galaxy rotation curves shapes. To this aim, we compare the distribution of galaxies of the SPARC sample, in the plane V2kpc-VRlast (V2kpc being the ...
Antonino Del Popolo, Morgan Le Delliou, Xiguo Lee   +2 more
doaj   +5 more sources

The M dwarf problem in the Galaxy [PDF]

Monthly Notices of the Royal Astronomical Society, 2012
We present evidence that there is an M dwarf problem similar to the previously identified G dwarf and K dwarf problems: the number of low-metallicity M dwarfs is not sufficient to match simple closed-box models of local Galactic chemical evolution.
Vincent M. Woolf, Andrew A. West
core   +7 more sources

A Possible “Too-many-satellites” Problem in the Isolated Dwarf Galaxy DDO 161 [PDF]

The Astrophysical Journal Letters
The abundance of satellite galaxies provides a direct test of ΛCDM and galaxy formation physics on small scales. While satellites of Milky Way-mass galaxies are well studied, those of dwarf galaxies remain largely unexplored.
Jiaxuan Li, Jenny E. Greene, Shany Danieli, Scott G. Carlsten, Marla Geha   +4 more
doaj   +5 more sources

Extension of M Dwarf Spectra Based on Adversarial AutoEncoder

Universe, 2021
M dwarfs are main sequence stars and they exist in all stages of galaxy evolution. As the living fossils of cosmic evolution, the study of M dwarfs is of great significance to the understanding of stars and the stellar populations of the Milky Way ...
Jiyu Wei, Xingzhu Wang, Bo Li, Yuze Chen, Bin Jiang   +4 more
doaj   +1 more source

Reconciling large- and small-scale structure in Twin Higgs models

Journal of High Energy Physics, 2017
We study possible extensions of the Twin Higgs model that solve the Hierarchy problem and simultaneously address problems of the large- and small-scale structures of the Universe.
Valentina Prilepina, Yuhsin Tsai
doaj   +1 more source

The M101 group complex: new dwarf galaxy candidates and spatial structure [PDF]

, 2017
The fine details of the large-scale structure in the local universe provide important empirical benchmarks for testing cosmological models of structure formation. Dwarf galaxies are key object for such studies.
Binggeli, Bruno, Jerjen, Helmut, Müller, Oliver, Scalera, Roberto   +3 more
core   +2 more sources

The Progenitors of Dwarf Spheroidal Galaxies [PDF]

, 2003
Dwarf spheroidal (dSph) galaxies present an evolutionary puzzle that we explore in 40 early- and late-type dwarfs in the Local Group and nearby field.
Bonifacio P., Carignan C., Daniel Harbeck, Davies J. I., de Boer K. S., Eskridge P. B., Eva K. Grebel, Grebel E. K., Hirashita H., Hirashita H., John S. Gallagher III, Karachentsev I., Koribalski B., Oort J. H., Phillipps S., Richer M., Skillman E. D., Tolstoy E.   +17 more
core   +3 more sources

NGC 4138 - A Case Study in Counterrotating Disk Formation [PDF]

, 1996
The Sa(r) galaxy NGC 4138 has been recently found to contain an extensive counterrotating disk which appears to be still forming. Up to a third of the stars in the disk system may be on retrograde orbits.
Adrick H. Broeils, Aniruddha R. Thakar, Barbara S. Ryden, Brahic A., Katherine P. Jore, Negroponte J., Roberts M. S., Thakar A. R.   +7 more
core   +2 more sources

Astrophysical site(s) of r-process elements in galactic chemodynamical evolution model

EPJ Web of Conferences, 2016
Astrophysical site(s) of rapid neutron-capture process (r-process) is (are) not identified yet. Although core-collapse supernovae have been regarded as one of the possible candidates of the astrophysical site of r-process, nucleosynthesis studies suggest
Hirai Yutaka, Ishimaru Yuhri, Saitoh Takayuki R., Fujii Michiko S., Hidaka Jun, Kajino Toshitaka   +5 more
doaj   +1 more source

Lambda-Cold Dark Matter, Stellar Feedback, and the Galactic Halo Abundance Pattern [PDF]

, 2005
(Abridged) The hierarchical formation scenario for the stellar halo requires the accretion and disruption of dwarf galaxies, yet low-metallicity halo stars are enriched in alpha-elements compared to similar, low-metallicity stars in dwarf spheroidal ...
Andreea S. Font, Bondi H., Brant Robertson, Devriendt J. E. G., Gratton R. G., Gratton R. G., Gratton R. G., Greggio L., Hill V., Hill V., Hill V., Hill V., James S. Bullock, Jasniewicz G., Kathryn V. Johnston, Lacey C., Lars Hernquist, Matteucci F., Matteucci F., Matteucci F., Moore B., Nissen P. E., Pagel B. E. J., Schaller G., Tinsley B. M., Tinsley B. M., Tsujimoto T., Unavane M.   +27 more
core   +2 more sources