Simulations of Galactic chemical evolution. I. O and Fe abundances in a simple collapse model.
Abstract
We use N-body/hydrodynamical simulations to investigate the chemical evolution of the Galaxy assuming that it forms by the collapse of a rotating cloud of gas and dark matter. Dissipative effects lead to the formation of a gaseous disk where stars are allowed to form in locally unstable regions. The global star formation rate (SFR) peaks at about 50Msun_/yr at the time of collapse and settles later to a roughly constant mean value of ~2Msun_/yr. We perform a detailed modeling of the expected rates and yields of type II (SNII) and type Ia (SNIa) supernovae to follow the metal enrichment history of this Galaxy model for 8Gyr. At this time, which we identify with the time of formation of the Sun, roughly two thirds of the Galactic iron have been synthesized in SNIa, while 98% of the Galactic oxygen is due to SNII events. Our results compare favorably with observational constraints such as the age-metallicity relation, the correlation between [O/Fe] and [Fe/H], and the O and Fe abundances in the solar neighborhood.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1996
- Bibcode:
- 1996A&A...315..105R
- Keywords:
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- METHODS: NUMERICAL;
- GALAXY: ABUNDANCES;
- GALAXY: EVOLUTION;
- GALAXY: FORMATION;
- GALAXY: KINEMATICS AND DYNAMICS