ar X iv : a st ro - p h / 05 08 69 3 v 1 3 1 A ug 2 00 5 Planetary nebulae and the chemical evolution of the galactic bulge
نویسندگان
چکیده
Electron temperatures, densities, ionic and elemental abundances of helium, nitrogen, oxygen, argon, sulfur and neon were derived for a sample of bulge planetary nebulae, representative of its intermediate mass population. Using these results as constraints, a model for the chemical evolution of the galactic bulge was developed. The results indicate that the best fit is achieved using a double-infall model, where the first one is a fast collapse of primordial gas and the second is slower and enriched by material ejected by the bulge itself during the first episode.
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