415 citations · 2.1k across the 27 of their papers we have counts for
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The Luminosity Function of bright QSOs at z~4 and implications for the cosmic ionizing background
K. Boutsia, A. Grazian, F. Fontanot +8
Based on results by recent surveys, the number of bright quasars at redshifts z>3 is being constantly revised upwards. Current consensus is that at bright magnitudes ($M_{1450}\le…
The spectroscopic follow-up of the QUBRICS bright quasar survey
K. Boutsia, A. Grazian, G. Calderone +11
We present the results of the spectroscopic follow up of the QUBRICS survey. The selection method is based on a machine learning approach applied to photometric catalogs, covering…
On the AGN nature of two UV bright sources at z_spec~5.5 in the CANDELS fields: an update of the AGN space density at M1450~-22.5
A. Grazian, E. Giallongo, F. Fiore +8
It is a widespread opinion that hydrogen reionization is mainly driven by primeval star-forming galaxies, with a minor role of high-z active galactic nuclei. Recent observations, h…
The Lyman continuum escape fraction and the Mean Free Path of hydrogen ionizing photons for bright z~4 QSOs from SDSS DR14
M. Romano, A. Grazian, E. Giallongo +5
One of the major challenges in observational cosmology is related to the redshift evolution of the average hydrogen ionization in the Universe. In order to probe the ionization lev…
The space densities and emissivities of AGNs at
E. Giallongo, A. Grazian, F. Fiore +11
The study of the space density of bright AGNs at has been subject to extensive effort given its importance for the estimate of the cosmological ionizing emissivity and growth…
Outflows in the Discs of Active Galaxies
N. Menci, F. Fiore, C. Feruglio +5
Recent advances in observations have provided a wealth of measurements of the expansions of outflows in galactic discs out to large radii in a variety of galactic hosts. To provide…