The Metal Absorption Systems of the Hubble Deep Field South QSO

Abstract

The Hubble Deep Field South (HDFS) has been recently selected, and the observations are planned for 1998 October. We present a high-resolution (FWHM ~= 14 km s^-1) spectrum of the quasar J2233-606 (z_em ~= 2.22), which is located 5.1‧ east of the HDFS. The spectrum obtained with the New Technology Telescope redward of the Lyalpha emission line covers the spectral range 4386-8270 Å. This range corresponds to redshift intervals for C iv and Mg ii intervening systems of z = 1.83-2.25 and z = 0.57-1.95, respectively. The data reveal the presence of two complex intervening C iv systems at redshift z = 1.869 and z = 1.943, and two complex associated (z_abs ~ z_em) systems. Two other C iv systems at z = 1.7865 and z = 2.077, suggested by the presence of strong Lyalpha lines in low-resolution ground-based and Hubble Space Telescope (HST) observations, have been identified. The system at z = 1.943 is also responsible for the Lyman limit absorption seen in the HST Space Telescope Imaging Spectrograph spectrum. The main goal of the present work is to provide astronomers interested in the HDFS program with information related to absorbing structures at high redshift, which are distributed along the nearby QSO line of sight. For this purpose, the reduced spectrum, obtained from 3 hr of integration time, has been released to the astronomical community. Based on observations obtained during program 60.B-0381 at the European Southern Observatory on La Silla, Chile.