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arXiv · 0806.2658

AGB Connection and Ultraviolet Luminosity Excess in Elliptical Galaxies

Alberto Buzzoni·Rosa A. Gonzalez-Lopezlira
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Abstract

Relying on infrared surface brightness fluctuactions to trace AGB properties in a sample of elliptical galaxies in the Virgo and Fornax clusters, we assess the puzzling origin of the "UV-upturn" phenomenon, recently traced down to the presence of a hot horizontal branch stellar component. We find that the UV-upturn actually signals a profound change in the c-m diagram of stellar populations in elliptical galaxies, involving both the hot stellar component and red-giant evolution.

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Alberto Buzzoni, Rosa A. Gonzalez-Lopezlira. 2008-06-16. AGB Connection and Ultraviolet Luminosity Excess in Elliptical Galaxies. https://doi.org/10.1086/589984

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