The Great Observatories Origins Deep Survey

VLT/FORS2 spectroscopy in the GOODS-South Field

¹ Dipartimento di Astronomia dell'Università di Padova, Vicolo dell'Osservatorio 2, 35122 Padova, Italy e-mail: evanzell@eso.org
² INAF - Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 40131 Trieste, Italy
³ National Optical Astronomy Obs., PO Box 26732, Tucson, AZ 85726, USA
⁴ ST-ECF, Karl-Schwarzschild Str. 2, 85748 Garching, Germany
⁵ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
⁶ European Southern Observatory, Karl-Schwarzschild-Strasse 2, Garching 85748, Germany
⁷ Jet Propulsion Laboratory, California Institute of Technology, MS 169-506, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
⁸ Université Paris-Sud XI, 15 rue Georges Clemenceau, 91405 Orsay Cedex, France
⁹ Kapteyn Instituut, Landleven 12, 9747 AD Groningen, The Netherlands

Received: 25 June 2004
Accepted: 14 December 2004

Abstract

We present the first results of the ESO/GOODS program of spectroscopy of faint galaxies in the Chandra Deep Field South (CDF-S). 399 spectra of 303 unique targets have been obtained in service mode with the FORS2 spectrograph at the ESO/VLT, providing 234 redshift determinations (the median of the redshift distribution is at 1.04). The typical redshift uncertainty is estimated to be . Galaxies have been color selected in a way that the resulting redshift distribution typically spans from to 2. The reduced spectra and the derived redshifts are released to the community through the ESO web page http://www.eso.org/science/goods/. Large scale structure is clearly detected at and 1.61. Three Lyman-break galaxies have also been included as targets and are confirmed to have redshifts , 4.882 and 5.828. In a few cases, we observe clear [OII]3727 rotation curves, even at the relatively low resolution () of the present observations. Assuming that the observed velocity structure is due to dynamically-relaxed rotation, this is an indication of large galactic masses (few times ) at .