Formation and evolution of the Galactic bulge: constraints from stellar abundances

Abstract

We present results for the chemical evolution of the Galactic bulge in the context of an inside-out formation model of the Galaxy. A supernova-driven wind was also included in analogy with elliptical galaxies. New observations of chemical abundance ratios and metallicity distribution have been employed in order to check the model results. We confirm previous findings that the bulge formed on a very short timescale with a quite high star formation efficiency and an initial mass function more skewed toward high masses than the one suitable for the solar neighbourhood. A certain amount of primary nitrogen from massive stars might be required to reproduce the nitrogen data at low and intermediate metallicities.