Optical-NIR spectra of quasars close to reionization (z~ 6)

Abstract

X-shooter, with its characteristics of resolution, spectral coverage and efficiency, provides a unique opportunity to obtain spectra of the highest-redshift quasars (z ~ 6) that will allow us to carry out successful investigations on key cosmological issues, from the details of the re-ionization process, to the evolution of the first galaxies and AGNs. In this paper, we present the spectra of three z ~ 6 quasars: one obtained during the commissioning of X-shooter and two in the context of our ongoing GTO programme. Combining this sample with data in the literature, we update the value of the C IV cosmic mass density in the range 4.5 < z < 5, confirming the constant trend with redshift between 2.5 and 5.

arXiv commentProceedings of the workshop "The first year with X-shooter" October 19-22 2010, Como, Italy. Accepted for publication in Astronomische Nachrichten. Typos corrected and reference updated

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Cited by in corpus (4)

• Metals in the IGM approaching the re-ionization epoch: results from X-shooter at the VLT
• Constraints on the Universal CIV Mass Density at z~6 from Early IR Spectra Obtained with the Magellan FIRE Spectrograph
• High-Redshift Metals. II. Probing Reionization Galaxies with Low-Ionization Absorption Lines at Redshift Six
• The role of galaxies and AGN in reionizing the IGM - II: metal-tracing the faint sources of reionization at $5\lesssim z\lesssim 6$