Abundances from a large spectroscopic survey in ω Centauri

ω Centauri, the largest globular cluster of our Milky Way, is an outstanding object in many aspects. Studies on the red giant branch (RGB) revealed a large spread in iron abundance, which ranges from [Fe/H]∼-2.0 to -0.4 dex and the existence of multiple sub-populations that do not only differ in their element abundances but also in their spatial and kinematic distributions (e.g. Norris et al. 1997). Furthermore more recent photometric studies suggested the existence of an age spread between these subpopulations (e.g. Hilker & Richtler 2000).