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arXiv · 1602.01842

The VIMOS Ultra Deep Survey First Data Release: spectra and spectroscopic redshifts of 698 objects up to z~6 in CANDELS

Abstract

This paper describes the first data release (DR1) of the VIMOS Ultra Deep Survey (VUDS). The DR1 includes all low-resolution spectroscopic data obtained in 276.9 arcmin2 of the CANDELS-COSMOS and CANDELS-ECFDS survey areas, including accurate spectroscopic redshifts z_spec and individual spectra obtained with VIMOS on the ESO-VLT. A total of 698 objects have a measured redshift, with 677 galaxies, two type-I AGN and a small number of 19 contaminating stars. The targets of the spectroscopic survey are selected primarily on the basis of their photometric redshifts to ensure a broad population coverage. About 500 galaxies have z_spec>2, 48 with z_spec>4, and the highest reliable redshifts reach beyond z_spec=6. This dataset approximately doubles the number of galaxies with spectroscopic redshifts at z>3 in these fields. We discuss the general properties of the sample in terms of the spectroscopic redshift distribution, the distribution of Lyman-alpha equivalent widths, and physical properties including stellar masses M_star and star formation rates (SFR) derived from spectral energy distribution fitting with the knowledge of z_spec. We highlight the properties of the most massive star-forming galaxies, noting the large range in spectral properties, with Lyman-alpha in emission or in absorption, and in imaging properties with compact, multi-component or pair morphologies. We present the catalogue database and data products. All data are publicly available and can be retrieved from a dedicated query-based database available at http://cesam.lam.fr/vuds.

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L. A. M. Tasca, O. Le Fevre, B. Ribeiro, R. Thomas, C. Moreau, P. Cassata, B. Garilli, V. Le Brun, B. C. Lemaux, D. Maccagni, L. Pentericci, D. Schaerer, E. Vanzella, G. Zamorani, E. Zucca, R. Amorin, S. Bardelli, L. P. Cassara, M. Castellano, A. Cimatti, O. Cucciati, A. Durkalec, A. Fontana, M. Giavalisco, A. Grazian, N. P. Hathi, O. Ilbert, S. Paltani, J. Pforr, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, D. Vergani, P. Capak, S. Charlot, T. Contini, S. de la Torre, J. Dunlop, S. Fotopoulou, L. Guaita, A. Koekemoer, C. Lopez-Sanjuan, Y. Mellier, M. Salvato, N. Scoville, Y. Taniguchi, P. W. Wang. 2016-02-04. The VIMOS Ultra Deep Survey First Data Release: spectra and spectroscopic redshifts of 698 objects up to z~6 in CANDELS. https://doi.org/10.1051/0004-6361/201527963

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