AGB Connection and Ultraviolet Luminosity Excess in Elliptical Galaxies

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.

13 pages & 13 figures -- To appear in the Astrophysical Journal (Sep '08 issue). Further info on SBF models at http://www.bo.astro.it/~eps/home.html

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Cited by in corpus (16)

• The ACS Fornax Cluster Survey. V. Measurement and Recalibration of Surface Brightness Fluctuations and a Precise Value of the Fornax--Virgo Relative Distance
• The Panchromatic Hubble Andromeda Treasury I: Bright UV Stars in the Bulge of M31
• The Mid-Infrared Luminosities of Normal Galaxies over Cosmic Time
• The SAURON project - XVIII. The integrated UV-linestrength relations of early-type galaxies
• The distance to NGC1316 (Fornax A): yet another curious case
• Tracers of stellar mass-loss. I. Optical and near-IR colours and surface brightness fluctuations
• Stellar lifetime and ultraviolet properties of the old metal-rich Galactic open cluster NGC6791: a pathway to understand the UV upturn of elliptical galaxies
• Revisiting binary stars in population synthesis models
• The GALEX Ultraviolet Virgo Cluster Survey (GUViCS). VII.: BCG UV upturn and the FUV-NUV color up to redshift 0.35
• The Next Generation Virgo cluster Survey (NGVS). XXVI. The issues of photometric age and metallicity estimates for globular clusters
• The SAURON project-XXI. The spatially-resolved UV-line strength relations of early-type galaxies
• VLT Optical BVR observations of two bright Supernova Ia hosts in the Virgo cluster
• The horizontal branch morphology of M31 globular clusters. Extreme second parameter effect in outer halo clusters
• GalevNB: a conversion from N-BODY simulations to observations
• An Empirical Connection between the UV Color of Early Type Galaxies and the Stellar Initial Mass Function
• UB CCD photometry of the old, metal rich, open clusters NGC 6791, NGC 6819 and NGC 7142