Abstract
A wide range of observational and theoretical arguments suggest that the universe experienced a period of heating and metal enrichment, most likely from starbursting dwarf galaxies. Using a hydrodynamic simulation, we have conducted a detailed theoretical investigation of this epoch at the end of the cosmological "dark ages." Outflows strip baryons from previralized halos with total masses ≲1010 M⊙, reducing their number density and the overall star formation rate, while pushing these quantities toward their observed values. We show that the metallicity of ≲ 1010 M⊙ objects increases with size but with a large scatter, reproducing the metallicity-luminosity relation of dwarf galaxies. Galaxies ≳ 1010 M⊙ form with a roughly constant initial metallicity of 10% solar, explaining the observed lack of metal-poor disk stars in these objects. Outflows enrich roughly 20% of the simulation volume, yielding a mean metallicity of 0.3% solar, in agreement with observations of C IV in quasi-stellar object absorption-line systems.
Original language | English (US) |
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Pages (from-to) | 836-843 |
Number of pages | 8 |
Journal | Astrophysical Journal |
Volume | 581 |
Issue number | 2 I |
DOIs | |
State | Published - Dec 20 2002 |
Externally published | Yes |
Keywords
- Galaxies: abundances
- Galaxies: dwarf
- Galaxies: evolution
- Galaxies: high-redshift
- Quasars: absorption lines
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science