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arXiv · 0707.0260

Near UV properties of Early-Type Galaxies at z~1

Sperello di Serego Alighieri·Alessandro Bressan
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Abstract

We have used spectral fits to SSP-based atmosphere models to derive an estimate of the average stellar age for an almost complete sample of 15 Early-Type Galaxies (ETG) at 0.88<z<1.3. The results are in only partial agreement with the age estimates previously obtained for the same objects from an analysis of the M/L_B ratio, derived from the Fundamental Plane (FP) parameters. In particular spectral fits seem to underestimate the age of the most luminous ETG, and therefore do not reproduce the downsizing effect, which is clear for the FP ages. We also analyse the relationship between the spectral-fit ages and various near-UV spectral indices.

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Sperello di Serego Alighieri, Alessandro Bressan. 2007-07-02. Near UV properties of Early-Type Galaxies at z~1. https://arxiv.org/abs/0707.0260

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