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arXiv · 1603.05479

The VLT LEGA-C Spectroscopic Survey: The Physics of Galaxies at a Lookback Time of 7 Gyr

A. van der Wel·K. Noeske·R. Bezanson·C. Pacifici·A. Gallazzi·M. Franx·J. C. Munoz-Mateos·E. F. Bell·G. Brammer·S. Charlot·P. Chauke·I. Labbe·M. V. Maseda·A. Muzzin·H. -W. Rix·D. Sobral·J. van de Sande·P. G. van Dokkum·V. Wild·C. Wolf
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Abstract

The Large Early Galaxy Census (LEGA-C) is a Public Spectroscopic Survey of $\sim3200$ $K$-band selected galaxies at redshifts $z=0.6-1.0$ with stellar masses M_star > 1e10M_sun, conducted with VIMOS on ESO's Very Large Telescope. The survey is embedded in the COSMOS field ($R.A. = 10h00$; $Dec.=+2\deg$). The 20-hour long integrations produce high-$S/N$ continuum spectra that reveal ages, metallicities and velocity dispersions of the stellar populations. LEGA-C's unique combination of sample size and depth will enable us for the first time to map the stellar content at large look-back time, across galaxies of different types and star-formation activity. Observations started in December 2014 and are planned to be completed by mid 2018, with early data releases of the spectra and value-added products. In this paper we present the science case, the observing strategy, an overview of the data reduction process and data products, and a first look at the relationship between galaxy structure and spectral properties, as it existed 7 Gyr ago.

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A. van der Wel, K. Noeske, R. Bezanson, C. Pacifici, A. Gallazzi, M. Franx, J. C. Munoz-Mateos, E. F. Bell, G. Brammer, S. Charlot, P. Chauke, I. Labbe, M. V. Maseda, A. Muzzin, H. -W. Rix, D. Sobral, J. van de Sande, P. G. van Dokkum, V. Wild, C. Wolf. 2016-03-17. The VLT LEGA-C Spectroscopic Survey: The Physics of Galaxies at a Lookback Time of 7 Gyr. https://doi.org/10.3847/0067-0049%2F223%2F2%2F29

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