Results 81 to 90 of about 34,432 (305)

Chemical and Photometric Evolution Models for Disk, Irregular, and Low Mass Galaxies

Advances in Astronomy, Volume 2014, Issue 1, 2014., 2014
We summarize the updated set of multiphase chemical evolution models performed with 44 theoretical radial mass initial distributions and 10 possible values of efficiencies to form molecular clouds and stars. We present the results about the infall rate histories, the formation of the disk, and the evolution of the radial distributions of diffuse and ...
Mercedes Mollá, Jorge Iglesias Páramo
wiley   +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

A FAST RADIO BURST IN THE DIRECTION OF THE CARINA DWARF SPHEROIDAL GALAXY [PDF]

, 2014
We report the real-time discovery of a fast radio burst (FRB 131104) with the Parkes radio telescope in a targeted observation of the Carina dwarf spheroidal galaxy.
V. Ravi, V. Ravi, V. Ravi, R. Shannon, A. Jameson   +4 more
semanticscholar   +1 more source

Chemodynamical Simulations of Dwarf Galaxy Evolution

Advances in Astronomy, Volume 2014, Issue 1, 2014., 2014
In this review I give a summary of the state of the art for what concerns the chemo‐dynamical numerical modelling of galaxies in general and of dwarf galaxies in particular. In particular, I focus my attention on (i) initial conditions, (ii) the equations to solve; (iii) the star formation process in galaxies, (iv) the initial mass function, (v) the ...
Simone Recchi, José Manuel Vílchez Medina   +1 more
wiley   +1 more source

An inefficient dwarf: chemical abundances and the evolution of the Ursa Minor dwarf spheroidal galaxy [PDF]

, 2015
We present detailed chemical element abundance ratios of 17 elements with eight
Uğur Ural, G. Cescutti, A. Koch, J. Kleyna, S. Feltzing, M. Wilkinson   +5 more
semanticscholar   +1 more source

Astronomical Signatures of Dark Matter

Advances in High Energy Physics, Volume 2014, Issue 1, 2014., 2014
Several independent astronomical observations in different wavelength bands reveal the existence of much larger quantities of matter than what we would deduce from assuming a solar mass to light ratio. They are very high velocities of individual galaxies within clusters of galaxies, higher than expected rotation rates of stars in the outer regions of ...
Paul Gorenstein, Wallace Tucker, Anselmo Meregaglia   +2 more
wiley   +1 more source

Young Globular Clusters and Dwarf Spheroidals [PDF]

, 1999
Most of the globular clusters in the main body of the Galactic halo were formed almost simultaneously. However, globular cluster formation in dwarf spheroidal galaxies appears to have extended over a significant fraction of a Hubble time.
Ambartsumian V. A., Blaauw A., Chaboyer B., Ferraro I., Fuhrmann K., Murphy B. W., Nissen P. E., Ortolani S., Rosenberg A., Sidney van den Bergh, Unavane M.   +10 more
core   +2 more sources

Carbon and nitrogen abundances of individual stars in the Sculptor dwarf spheroidal galaxy [PDF]

, 2015
We present [C/Fe] and [N/Fe] abundance ratios and CH(lambda 4300) and S(lambda 3883) index measurements for 94 red giant branch (RGB) stars in the Sculptor dwarf spheroidal galaxy from VLT/VIMOS MOS observations at a resolving power R = 1150 at 4020 A ...
C. Lardo, G. Battaglia, E. Pancino, D. Romano, T. D. Boer, E. Starkenburg, E. Tolstoy, M. Irwin, P. Jablonka, M. Tosi   +9 more
semanticscholar   +1 more source

Deep photometry of the Draco dwarf spheroidal galaxy [PDF]

The Astronomical Journal, 1986
We report the results of deep CCD photometry of two overlapping fields in the Draco dwarf spheroidal galaxy. We find (B-V)o,g = m0.69, indicating a mean [Fe/H] = −2.0. The width of the giant branch below the horizontal branch is somewhat wider than our observational errors permit, from which we infer there is a spread in metallicities amongst the Draco
Bruce W. Carney, P. Seitzer
openaire   +1 more source

Intermediate Mass Black Holes: Their Motion and Associated Energetics

Advances in High Energy Physics, Volume 2014, Issue 1, 2014., 2014
There is a lot of current astrophysical evidence and interest in intermediate mass black holes (IMBH), ranging from a few hundred to several thousand solar masses. The active galaxy M82 and the globular cluster G1 in M31, for example, are known to host such objects.
C. Sivaram, Kenath Arun, Christian Corda
wiley   +1 more source