Light and Heavy Elements in the Galactic Bulge

Abstract

The chemical evolution of the Galactic bulge is treated here in the context of an inside-out model for the Galaxy formation. We assume that this central region evolved even faster than the Galactic halo and test the effect of changing the slope of the IMF on the predicted stellar metallicity distribution for bulge stars. An IMF favoring the formation of massive stars is found to improve the agreement with the most recently observed metallicity distribution of bulge K giants. Then, we make specific predictions about temporal evolution of several light and heavy species in the Galactic bulge. We predict that alpha-elements should be enhanced relative to Fe for most of the [Fe/H] range, with different degrees of enhancement due to the different nucleosynthetic history of each element, and show that Lithium abundance should follow a trend with metallicity similar to that found for the solar neighbourhood. Several possible stellar Li sources are discussed.