Title:

Cosmic Chemical Evolution and the Mean Metallicity of the Universe


Francesca Matteucci
Universita di Trieste



Abstract:

The chemical evolution of galaxies of different morphological type
(ellipticals, sprirals and irregulars) will be described. In
particular, the predictions concerning abundances and abundance
ratios of the most common chemical elements (H, He, C, N, O,
alpha-elements, Fe) will be discussed and compared to the
observational data.  Abundance ratios of particular elements such as
alpha/Fe will be used to infer the nature and the age of
high-redshift objects. Finally, by taking into account the
contributions of all galactic types, we will show the cosmic
evolution of element production (especially metals) and an estimate
of the mean metallicity of the universe will be provided by
considering stars, ISM, ICM and IGM.

>