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Hierarchical structure formation and chemical evolution of damped Lyα systems

Qian, Y.-Z. and Wasserburg, G. J. (2003) Hierarchical structure formation and chemical evolution of damped Lyα systems. Astrophysical Journal Letters, 596 (1). L9-L12. ISSN 2041-8205. doi:10.1086/379144.

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We present a model for the chemical evolution of damped Lyα systems considering the production of "metals" by Type II supernovae and infall associated with hierarchical structure formation. The growth of metallicity in these systems is a reflection of the competition between astration and infall. The apparent late turn-on of these systems is due to the late cutoff of infall. The wide range in [Fe/H] at a given redshift is explained by the range of the times for the onset of star formation and the range of the times for infall cessation in different systems. The observed lower bound of [Fe/H] ≈ -3 follows from the very rapid initial rise of [Fe/H] subsequent to the onset of star formation. To reach [Fe/H] ≈ -3 from a metal-free initial state requires only ~30 Myr, so the probability of observing lower [Fe/H] values is very small.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper DOIArticle
Wasserburg, G. J.0000-0002-7957-8029
Additional Information:© 2003 The American Astronomical Society. Received 2003 July 11; accepted 2003 August 19; published 2003 September 18. We wish to dedicate this Letter to Allan Sandage for galaxies of reasons. We thank Jason Prochaska for making available the new data that stimulated us to further consider DLA systems. Intense questioning by Michael Norman on the requirement of VMSs and a prompt inventory in our earlier models also provided a great stimulus. This work was supported in part by DOE grants DE-FG02-87ER40328, DE-FG02-00ER41149 (Y. Z. Q.), and DE-FG03-88ER13851 (G. J. W.), Caltech Division Contribution 8906(1108).
Funding AgencyGrant Number
Department of Energy (DOE)DE-FG02-87ER40328
Department of Energy (DOE)DE-FG02-00ER41149
Department of Energy (DOE)DE-FG03-88ER13851
Subject Keywords:galaxies: abundances—galaxies: evolution—intergalactic medium
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological and Planetary Sciences8906
Lunatic Asylum Lab1108
Issue or Number:1
Record Number:CaltechAUTHORS:20131113-103654887
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Official Citation:Hierarchical Structure Formation and Chemical Evolution of Damped Lyα Systems Y.-Z. Qian and G. J. Wasserburg 2003 ApJ 596 L9
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42423
Deposited By: Tony Diaz
Deposited On:13 Nov 2013 22:46
Last Modified:10 Nov 2021 16:22

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