The chemical evolution of the Galactic Bulge seen through micro-lensing   events
  Galactic bulges are central to understanding galaxy formation and evolution. Here we report on recent studies using micro-lensing events to obtain spectra of high resolution and moderately high signal-to-noise ratios of dwarf stars in the Galactic bulge. Normally this is not feasible for the faint turn-off stars in the Galactic bulge, but micro-lensing offers this possibility. Elemental abundance trends in the Galactic bulge as traced by dwarf stars are very similar to those seen for dwarf stars in the solar neighbourhood. We discuss the implications of the ages and metallicity distribution function derived for the micro-lensed dwarf stars in the Galactic bulge. 
Sofia Feltzing, Thomas Bensby, Jorge Mel\'endez, Daniel Ad\'en, Martin   Asplund, Andy Gould, Jennifer Johnson, Sara Lucatel...
astro-ph.GA