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arXiv · 1101.1948

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

V. D'Odorico·G. Cupani·S. Cristiani·R. Maiolino·P. Molaro·M. Nonino·A. Cimatti·S. di Serego Alighieri·F. Fiore·A. Fontana·S. Gallerani·E. Giallongo·F. Mannucci·A. Marconi·L. Pentericci·M. Viel·G. Vladilo
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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.

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V. D'Odorico, G. Cupani, S. Cristiani, R. Maiolino, P. Molaro, M. Nonino, A. Cimatti, S. di Serego Alighieri, F. Fiore, A. Fontana, S. Gallerani, E. Giallongo, F. Mannucci, A. Marconi, L. Pentericci, M. Viel, G. Vladilo. 2011-01-10. Optical-NIR spectra of quasars close to reionization (z~ 6). https://doi.org/10.1002/asna.201111545

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