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Accession Number DE2012-1046375
Title Radio and Optical Luminosity Evolution of Quarsars II-The SDSS Sample.
Publication Date Jul 2012
Media Count 14p
Personal Author A. Lawrence J. Singal L. Stawarz V. Petrosian
Abstract 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.
Keywords Distribution
Luminosity
Optical properties
Parameters
Quasars
Radio astronomy


 
Source Agency Technical Information Center Oak Ridge Tennessee
NTIS Subject Category 46 - Physics
54C - Astrophysics
Corporate Author Stanford Linear Accelerator Center, CA.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1303
Contract Number DE-AC02-76SF00515

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