A survey of luminous high-redshift quasars with SDSS and WISE II. the bright end of the quasar luminosity function at z ~ 5
| Title: | A survey of luminous high-redshift quasars with SDSS and WISE II. the bright end of the quasar luminosity function at z ~ 5 |
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| Authors: | Yang, Jinyi, Wang, Feige, Wu, Xue-Bing, Fan, Xiaohui, McGreer, Ian D., Bian, Fuyan, Yi, Weimin, Yang, Qian, Ai, Yanli, Dong, Xiaoyi, Zuo, Wenwen, Green, Richard, Jiang, Linhua, Wang, Shu, Wang, Ran, Yue, Minghao |
| Publication Year: | 2016 |
| Collection: | Astrophysics |
| Subject Terms: | Astrophysics - Astrophysics of Galaxies |
| More Details: | This is the second paper in a series on a new luminous z ~ 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 ~ 5. Combined our 45 new quasars with previously known quasars that satisfy our selections, we construct the largest uniform luminous z ~ 5 quasar sample to date, with 99 quasars in the range 4.7 <= z < 5.4 and -29 < M1450 <= -26.8, within the Sloan Digital Sky Survey (SDSS) footprint. We use a modified 1/Va 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 (LEDE) model. Using the best fit QLF, the contribution of quasars to the ionizing background at z ~ 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. Comment: 14 pages, 12 figures, Accepted by ApJ |
| Document Type: | Working Paper |
| DOI: | 10.3847/0004-637X/829/1/33 |
| Access URL: | http://arxiv.org/abs/1607.04415 |
| Accession Number: | edsarx.1607.04415 |
| Database: | arXiv |
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