English
Related papers

Related papers: Metals and ionizing photons from dwarf galaxies

200 papers

Cosmological simulations of Population III star formation suggest an initial mass function (IMF) biased toward very massive stars (M>100Msun) formed in minihalos at redshift z>20, when the cooling is driven by molecular hydrogen. However,…

Astrophysics of Galaxies · Physics 2015-05-13 Michele Trenti , Michael Shull

We present a new semi-analytical model of the population of satellite galaxies of the Milky Way, aimed at estimating the effect of the geometry of reionization at galaxy scale on the properties of the satellites. In this model reionization…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 P. Ocvirk , D. Aubert

Baryonic cycling is reflected in the spatial distribution of metallicity within galaxies, yet gas-phase metallicity distribution and its connection with other properties of dwarf galaxies are largely unexplored. We present the first…

We present a revised metallicity distribution of dwarfs in the solar neighbourhood. This distribution is centred on solar metallicity. We show that previous metallicity distributions, selected on the basis of spectral type, are biased…

Astrophysics · Physics 2009-11-06 Misha Haywood

We have measured the mass of metals in the molecular gas in 13 submillimetre galaxies at z~4 in which the gas, based on previous observations, lies in a cold rotating disk. We measured the metal masses using either the submillimetre line or…

Astrophysics of Galaxies · Physics 2024-06-24 Stephen Eales , Haley Gomez , Loretta Dunne , Simon Dye , Matthew W. L. Smith

We investigate the metal enrichment of the intracluster medium (ICM) in the framework of hierarchical models of galaxy formation. We calculate the formation and evolution of galaxies and clusters using a semi-analytical model which includes…

To account for the observed differential metallicity distribution (DMD) of the Milky Way halo, a semi-analytical model is presented in the framework of the hierarchical merging paradigm for structure formation. It is assumed that the Milky…

Astrophysics · Physics 2009-11-13 Nikos Prantzos

We investigate stellar metallicity distribution functions (MDFs), including Fe and ${\alpha}$-element abundances, in dwarf galaxies from the Feedback in Realistic Environments (FIRE) project. We examine both isolated dwarf galaxies and…

Nearby dwarf galaxies exhibit tight correlations between their global stellar and dynamical properties, such as circular velocity, mass-to-light ratio, stellar mass, surface brightness, and metallicity. Such correlations have often been…

Astrophysics · Physics 2010-11-11 Konstantinos Tassis , Andrey V. Kravtsov , Nickolay Y. Gnedin

Twenty years of high-resolution spectroscopy at the 8-10 m class telescopes have drastically expanded our view of the gas-phase metallicity in the z>2 universe. This contribution briefly summarizes how these studies reveal a widespread…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-20 Michele Fumagalli

We investigate the process of reionisation in a model in which the dark matter is a warm elementary particle such as a sterile neutrino. We focus on models that are consistent with the dark matter decay interpretation of the recently…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Sownak Bose , Carlos S. Frenk , Hou Jun , Cedric G. Lacey , Mark R. Lovell

Observations have established that the diffuse intergalactic medium (IGM) at z ~ 3 is enriched to ~0.1-1% solar metallicity and that the hot gas in large clusters of galaxies (ICM) is enriched to 1/3-1/2 solar metallicity at z=0. Metals in…

Massive rotating single stars with an initial metal composition appropriate for the dwarf galaxy I Zw 18 ([Fe/H]=$-$1.7) are modelled during hydrogen burning for initial masses of 9-300 M$_{\odot}$ and rotational velocities of 0-900 km…

Solar and Stellar Astrophysics · Physics 2015-08-26 D. Szécsi , N. Langer , S. -C. Yoon , D. Sanyal , S. de Mink , C. J. Evans , T. Dermine

We use 112 N-body/hydrodynamical simulations in the standard Cold Dark Matter universe, to follow the formation of galaxy-sized halos and investigate the chemical enrichment of both the stellar component and the interstellar medium of…

Astrophysics · Physics 2015-05-13 Mustapha Mouchine , Brad K. Gibson , Agostino Renda , Daisuke Kawata

Metal-poor stars in the Milky Way are local relics of the epoch of the first stars and the first galaxies. However, a low metallicity does not prove that a star formed in this ancient era, as metal-poor stars form over a range of redshift…

Solar and Stellar Astrophysics · Physics 2015-09-07 Andrew R. Casey , Kevin C. Schlaufman

We estimate the maximum contribution to reionization from the first generation of massive stars, with zero metallicity, under the assumption that one of these stars forms with a fixed mass in every collapsed halo in which metal-free gas is…

Astrophysics · Physics 2007-05-23 Jose M. Rozas , Jordi Miralda-Escude , Eduard Salvador-Sole

We use a new method to trace backwards the star formation history of the Milky Way disk, using a sample of M dwarfs in the solar neighbourhood which is representative for the entire solar circle. M stars are used because they show H_alpha…

Astrophysics · Physics 2009-11-13 B. Fuchs , H. Jahreiss , C. Flynn

Gas flows play a fundamental role in galaxy formation and evolution, providing the fuel for the star formation process. These mechanisms leave an imprint in the amount of heavy elements. Thus, the analysis of this metallicity signature…

Astrophysics of Galaxies · Physics 2016-04-20 Morgane Cousin , Véronique Buat , Samuel Boissier , Matthieu Béthermin , Yannick Roehlly , Mathieu Génois

Observational studies are finding stars believed to be relics of the earliest stages of hierarchical mass assembly of the Milky Way (i.e., proto-Galaxy). In this work, we contextualize these findings by studying the masses, ages, spatial…