2012/07/31 by J. Singal, V. Petrosian, L. Stawarz +1 · 1 citation
Physics and Astronomy · #astro-ph.CO
paper · pdf · doi:10.1088/0004-637x/764/1/43
published as ApJ, 2013, 764, 43 · 16 pages, 17 figures, 1 table. Updated to journal version. arXiv admin note: substantial text overlap with arXiv:1101.2930
arxiv created 2013/01/14 · arxiv updated 2015/06/05
We determine the radio and optical luminosity evolutions and the true distribution of the radio loudness parameter R, defined as the ratio of the radio to optical luminosity, for a set of more than 5000 quasars combining SDSS optical and FIRST radio data. We apply the method of Efron and Petrosian to access the intrinsic distribution parameters, taking into account the truncations and correlations inherent in the data. We find that the population exhibits strong positive evolution with redshift in both wavebands, with somewhat greater radio evolution than optical. With the luminosity evolutions accounted for, we determine the density evolutions and local radio and optical luminosity functions. The intrinsic distribution of the radio loudness parameter R is found to be quite different than the observed one, and is smooth with no evidence of a bi-modality in radio loudness. The results we find are in general agreement with the previous analysis of Singal et al. 2011 which used POSS-I optical and FIRST radio data.