Radio Luminosity, Black Hole Mass and Eddington Ratio for Quasars from the Sloan Digital Sky Survey

Abstract

We investigate the M-BH-sigma* relation for radio-loud quasars with redshift z < 0.83 in Data Release 3 of the Sloan Digital Sky Survey (SDSS). The sample consists of 3772 quasars with better models of the H beta and [O III] lines and available radio luminosity, including 306 radio-loud quasars, 3466 radio-quiet quasars with measured radio luminosity or upper-limit of radio luminosity (181 radio-quiet quasars with measured radio luminosity). The virial supermassive black hole mass (M-BH) is calculated from the broad H beta line, and the host stellar velocity dispersion (sigma*) is traced by the core [O III] gaseous velocity dispersion. The radio luminosity and radio loudness are derived from the FIRST catalog. Our results are as follows: (1) For radio-quiet quasars, we confirm that there is no obvious deviation from the M-BH-sigma* relation defined for inactive galaxies when the uncertainties in M-BH and the luminosity bias are concerned. (2) We find that the radio-loud quasars deviate more from the M-BH-sigma* relation than do the radio-quiet quasars. This deviation is only partly due to a possible cosmological evolution of the M-BH-sigma* relation and the luminosity bias. (3) The radio luminosity is proportional to M-BH(1.28-0.16+.023) (L-Bol/L-Edd)(1.29-0.24+0.31) for radio-quiet quasars and to M-BH(3.10-0.70+0.60) (L-Bol/L-Edd)(4.18-1.10+1.40) for radio-loud quasars. The weaker dependence of the radio luminosity on the mass and the Eddington ratio for radio-loud quasars shows that other physical effects would account for their radio luminosities, such as the spin of the black hole.