Abstract
view Abstract Citations (31) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Differential Evolution of Radio Quiet and Radio Loud Quasars Schmidt, Maarten ; van Gorkom, J. H. ; Schneider, Donald P. ; Gunn, James E. Abstract We have observed 40 optically selected high-redshift quasars with the VLA at 1515 MHz (20 cm). Three quasars are detected above our 3σ limit of 0.2 mJy. We review all available evidence on radio detections of optically selected quasars in terms of their ratio R of radio to optical luminosity. We find that the quasars ranked in the top 5-20 percent in R show strong evolution in their R distribution. We present two interpretations of this phenomenon. The first one poses that the R values decrease by a factor of around 100 from redshift 0.3 to 1.3. In the second interpretation, we consider that there are two populations of quasars, which we call radio silent and radio active, separated by R~0.1. The radio-silent fraction of quasars increases from ~16% at redshift 0.3, to ~75% at redshift 1.3. Publication: The Astronomical Journal Pub Date: February 1995 DOI: 10.1086/117292 Bibcode: 1995AJ....109..473S Keywords: Galactic Evolution; Luminosity; Quasars; Radio Astronomy; Radio Observation; Red Shift; Astronomical Spectroscopy; Statistical Analysis; Very Large Array (Vla); Astronomy; GALAXIES: DISTANCES AND REDSHIFTS; GALAXIES: EVOLUTION; QUASARS: GENERAL full text sources ADS | data products SIMBAD (40) NED (40)
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