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.
|Titolo:||Optical-NIR spectra of quasars close to reionization (z ∼ 6)|
|Data di pubblicazione:||2011|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/asna.201111545|
|Parole Chiave:||astro-ph.CO; astro-ph.CO|
|Appare nelle tipologie:||1.1 Articolo in rivista|