Comparing Chemical Abundances of the Damped Lyα Systems and Metal-Poor Stars
نویسنده
چکیده
I briefly draw comparisons between the fields of damped Lyα and metal-poor stellar abundances. In particular, I examine their complementary age-metallicity relations and comparisons between the damped Lyα and dwarf galaxy abundance patterns. Regarding the latter, I describe a series of problems concerning associating high z damped Lyα systems with present-day dwarfs.
منابع مشابه
The most metal-poor damped Lyα systems: insights into chemical evolution in the very metal-poor regime
We present a high spectral resolution survey of the most metal-poor damped Lyα absorption systems (DLAs) aimed at probing the nature and nucleosynthesis of the earliest generations of stars. Our survey comprises 22 systems with iron abundance less than 1/100 solar; observations of seven of these are reported here for the first time. Together with recent measures of the abundances of C and O in ...
متن کاملTHE UCSD HIRES/KECKI DAMPED Lyα ABUNDANCE DATABASE II. THE IMPLICATIONS
We present a comprehensive analysis of the damped Lyα abundance database presented in the first paper of this series. This database provides a homogeneous set of abundance measurements for many elements including Si, Cr, Ni, Zn, Fe, Al, S, Co, O, and Ar from 38 damped Lyα systems with zabs > 1.5. With little exception, these damped Lyα systems exhibit very similar relative abundances. There is ...
متن کاملNEW DAMPED Lyα METALLICITIES FROM ESI SPECTROSCOPY OF FIVE PALOMAR SKY SURVEY QUASARS
This paper presents chemical abundance measurements for 12 new z > 3 damped Lyα systems discovered toward five quasars from the Palomar Sky Survey. We determine H I column densities from profile fits to the observed damped Lyα profiles and measure ionic column densities and limits for all observed metal-line transitions. This dataset, acquired with the Echellette Spectrograph and Imager on the ...
متن کاملON THE EVOLUTION OF DAMPED Lyα SYSTEMS TO GALACTIC DISKS
The mean metallicity of the thick disk of the Galaxy is 0.5 dex higher than that of the damped Lyα systems. This has been interpreted to argue that stars in the former do not arise out of gas in the latter. Using new metallicity and H I column-density data we show the metal-rich damped systems do contain sufficient baryons at the thick-disk metallicity to account for the stellar masses of thick...
متن کاملThe explosion energy of early stellar populations: the Fe-peak element ratios in low-metallicity damped Lyα systems
The relative abundances of the Fe-peak elements (Ti–Zn) at the lowest metallicities are intimately linked to the physics of core-collapse supernova explosions. With a sample of 25 very metal poor damped Lyα systems (DLAs), we investigate the trends of the Fe-peak element ratios with metallicity. For nine of the 25 DLAs, a direct measurement (or useful upper limit) of one or more of the Ti, Cr, ...
متن کامل