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arXiv · 0901.3123

The Evolution of Field Early-Type Galaxies in the FDF and WHDF

Alexander Fritz·Asmus Boehm·Bodo L. Ziegler
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Abstract

We explore the properties of 24 field early-type galaxies at 0.20 =-0.74\pm0.08. The M/L evolution of these field galaxies suggests a continuous mass assembly of field early-type galaxies during the last 5 Gyr, that gets support by recent studies of field galaxies up to z~1. Independent evidence for recent SF activity is provided by spectroscopic (OII em., Hdelta) and photometric (rest-frame colors) diagnostics. Based on the Hdelta absorption feature we detect a weak residual SF for galaxies that accounts for 5%-10% in the total stellar mass of these galaxies. The co-evolution in the luminosity and mass of our galaxies favours a downsizing formation process. We find some evidence that our galaxies experienced a period of SF quenching, possible triggered by AGN activity that is in good agreement with recent results on both observational and theoretical side. (abridged)

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Alexander Fritz, Asmus Boehm, Bodo L. Ziegler. 2009-01-20. The Evolution of Field Early-Type Galaxies in the FDF and WHDF. https://doi.org/10.1111/j.1365-2966.2008.14241.x

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