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arXiv · 0708.0193

UV excess and AGB evolution in elliptical-galaxy stellar populations

Rosa A. Gonzalez-Lopezlira·A. Buzzoni
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Abstract

The puzzling origin of the ``UV-upturn'' phenomenon, observed in some elliptical galaxies, has recently been settled by identifying hot HB stars as main contributors to galaxy ultraviolet luminosity excess. While a blue HB morphology seems a natural characteristic of metal-poor stellar populations, its appearence in metal-rich systems, often coupled with a poorer rate of planetary nebulae per unit galaxy luminosity, might be calling for an intimate connection between UV excess and AGB properties in early-type galaxies. In this work, we want to briefly assess this issue, relying on infrared surface brightness fluctuations as a powerful tool to trace AGB properties in external galaxies with unresolved stellar populations.

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Rosa A. Gonzalez-Lopezlira, A. Buzzoni. 2007-08-01. UV excess and AGB evolution in elliptical-galaxy stellar populations. https://arxiv.org/abs/0708.0193

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