A SURVEY OF LUMINOUS HIGH-REDSHIFT QUASARS WITH SDSS AND WISE . II. THE BRIGHT END OF THE QUASAR LUMINOSITY FUNCTION AT z ∼ 5

This is the second paper in a series on a new luminous z similar to 5 quasar survey using optical and near-infrared colors. Here we present a new determination of the bright end of the quasar luminosity function (QLF) at z similar to 5. Combining. our 45 new quasars with previously known quasars that satisfy our selections, we construct the largest uniform luminous z similar to 5 quasar sample to date, with 99 quasars in the range of 4.7 <= z < 5.4 and -29 < M-1450 <= -26.8, within the Sloan Digital Sky Survey (SDSS) footprint. We use a modified 1/V-a method including flux limit correction to derive a binned QLF, and we model the parametric QLF using maximum likelihood estimation. With the faint-end slope of the QLF fixed as alpha = -2.03 from previous deeper samples, the best fit of our QLF gives a flatter bright end slope beta = -3.58 +/- 0.24 and a fainter break magnitude M-1450(*) = -26.98 +/- 0.23 than previous studies at similar redshift. Combined with previous work at lower and higher redshifts, our result is consistent with a luminosity evolution and density evolution model. Using the best-fit QLF, the contribution of quasars to the ionizing background at z similar to 5 is found to be 18%-45% with a clumping factor C of 2-5. Our sample suggests an evolution of radio loud fraction with optical luminosity but no obvious evolution with redshift.NSFC [11373008, 11533001]; Strategic Priority Research Program " The Emergence of Cosmological Structures" of the Chinese Academy of Sciences [XDB09000000]; National Key Basic Research Program of China [2014CB845700]; Ministry of Science and Technology of China [2016YFA0400703]; US NSF grant [AST 11-07682]; Chinese Academy of Sciences; People's Government of Yunnan Province; Strategic Priority Research Program "The Emergence of Cosmological Structures" [XDB09000000]; National Astronomical Observatories, Chinese Academy of Sciences; Special Fund for Astronomy from the Ministry of Finance in China; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences; Alfred P. Sloan Foundation; National Science Foundation; U.S. Department of Energy Office of Science; University of Arizona; Brazilian Participation Group; Brookhaven National Laboratory; University of Cambridge; Carnegie Mellon University; University of Florida; French Participation Group; German Participation Group; Harvard University; Instituto de Astrofisica de Canarias; Michigan State/Notre Dame/JINA Participation Group; Johns Hopkins University; Lawrence Berkeley National Laboratory; Max Planck Institute for Astrophysics; Max Planck Institute for Extraterrestrial Physics; New Mexico State University; New York University; Ohio State University; Pennsylvania State University; University of Portsmouth; Princeton University; Spanish Participation Group; University of Tokyo; University of Utah; Vanderbilt University; University of Virginia; University of Washington; Yale University; National Aeronautics and Space AdministrationNo embargo.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu