相关论文: The chemical evolution of galaxies causing damped …
We have collected data for 69 Damped Lyman-alpha (DLA) systems, to investigate the chemical evolution of galaxies in the redshift interval 0.0 < z < 4.4. In doing that, we have adopted the most general approach used so far to correct for…
A new method is presented for recovering the abundances of Damped Ly alpha systems (DLAs) taking into account the effects of dust depletion. For the first time, possible variations of the chemical composition of the dust are taken into…
The manner the galaxy accretes matter along with the star formation rates at different epochs, influence the evolution of the stable isotopic inventories of the galaxy. A detailed analysis is presented here to study the dependence of the…
The chemical composition of gas in galaxies can be measured in detail from absorption spectroscopy. By studying gas in galaxies in this way, it is possible to investigate the small and faint galaxies, which are the most numerous in the…
Since stellar populations enhance particular element abundances according to the yields and lifetimes of the stellar progenitors, the chemical evolution of galaxies serves as one of the key tools that allows the tracing of galaxy evolution.…
The evolution of the content of heavy elements in galaxies, the relative chemical abundances, their spatial distribution, and how these scale with various galactic properties, provide unique information on the galactic evolutionary…
Standard chemical evolution models based on long-term infall are affected by a number of problems, evidenced by the analysis of the most recent data. Among these: (1) models rely on the local metallicity distribution, assuming its shape is…
Utilizing a new, high mass resolution hydrodynamic simulation we compute the metallicity evolution of damped Lyman alpha systems (DLAs) and find a reasonable agreement with observations. In particular, the observed slow evolution of the DLA…
We investigate the absorption features associated with a gas-rich dwarf galaxy using cosmological hydrodynamics simulations. Our goal is to explore whether the progenitors of the lowest mass dwarf galaxies known to harbor neutral hydrogen…
Essentially all high-redshift galaxies show evidence for strong large-scale outflows that should have a profound effect on the structure and kinematics of both the galaxies themselves and their environment. The interstellar absorption…
Spectroscopy of QSO absorption lines provides essential observational input for the study of nucleosynthesis and chemical evolution of galaxies at high redshift. But new observations may indicate that present chemical abundance data are…
We present a model for the Lyman-alpha absorbers that treats all objects (from the low-density forest clouds to the dense damped systems) in a unified description. This approach is consistent with an earlier model of galaxies (luminosity…
The hypothesis that the Damped Ly-alpha systems (DLAs) are large, galactic disks (Milky Way sized) is tested by confronting predictions of models of the formation and evolution of (large) disk galaxies with observations, in particular the…
We study the formation of damped \lya and Lyman limit absorbers in a hierarchical clustering scenario using a gas dynamical simulation of an $\Omega = 1$, cold dark matter universe. In the simulation, these high column density systems are…
We show that the recently observed elemental abundance pattern of the carbon-rich metal-poor Damped Lyman $\alpha$ (DLA) system is in excellent agreement with the nucleosynthesis yields of faint core-collapse supernovae of primordial stars.…
We investigate the population of z=3 damped Lyman alpha absorbers (DLAs) in a recent series of high resolution galaxy formation simulations. The simulations are of interest because they form at z=0 some of the most realistic disk galaxies…
Some aspects of the chemical evolution of late-type dwarf galaxies are reviewed, together with their implications on three issues of cosmological relevance: similarity to primeval galaxies, derivation of the primordial helium abundance,…
We present Cosmic Origins Spectrograph (COS) measurements of metal abundances in eight 0.083<z<0.321 damped Lyman-\alpha (DLA) and sub-damped Ly-\alpha\ absorption systems serendipitously discovered in the COS-Halos survey. We find that…
Some results from an imaging program to identify low-redshift (0.09<z<1.63) damped Lyman-alpha (DLA) galaxies are presented. The standard paradigm that was widely accepted a decade ago, that DLA galaxies are the progenitors of luminous disk…
The chemical evolution of galaxies is investigated within the framework of the star formation rate (SFR) dependent integrated galactic initial mass function (IGIMF). We study how the global chemical evolution of a galaxy and in particular…