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Exploring the Lyman Forest with VLT/UVES

S. Cristiani·S. Bianchi·S. D'Odorico·T. -S. Kim
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Abstract

A sample of 8 QSOs with 1.7 < z_em < 3.7 has been observed with VLT/UVES at a typical resolution 45000 and S/N~40-50. Thanks to the two-arm design of the spectrograph, a remarkable efficiency has been achieved below 400nm and above 800nm, which translates immediately in the possibility of obtaining new results, especially at z<2.5. We report here new insight gained about the evolution of the number density of Ly-a lines, their column density distribution, the ionizing UV background and the cosmic baryon density.

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S. Cristiani, S. Bianchi, S. D'Odorico, T. -S. Kim. 2001-09-19. Exploring the Lyman Forest with VLT/UVES. https://arxiv.org/abs/astro-ph/0109305

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