Previous abstract Next abstract

Session 25 - Galaxies, Clusters of Galaxies and their Evolution.
Oral session, Monday, June 08

[25.07] Galactic Chemical Evolution at Low Metallicity

L. Saleh, T. Beers (Michigan State Univ.), G. J. Mathews (Univ. of Notre Dame)

We have developed a chemical evolution model to account for elemental abundances of metal-poor stars in the galactic halo. The simplest version of the model consists of closed star-forming proto-galactic clouds of initially primordial composition that are self enriched. We also consider effects of stellar winds from starforming regions and the mixing/cooling of the hot stellar ejecta within the evaporating cloud. The low metallicity early enrichment is dominated by massive stars, hence, we utilize stellar nucleosynthesis yields (from H to Zn) given by the m > 10 M_ødot models of Woosley and Weaver (1995). We also consider possible variations of the initial mass function. These models are compared with the low metallicity data of Ryan et al. (1996). Implications of these studies for the early evolution of the Galaxy will be discussed.

Program listing for Monday