Basic properties of Fermi blazars and the ‘blazar sequence’

Abstract

By statistically analysing a large sample that includes Fermi-detected blazars (FBs) and non-Fermi-detected blazars (NFBs), we find that there are significant differences between FBs and NFBs in redshift, black hole mass, jet kinetic power from cavity power, broad-line luminosity and the ratio of core luminosity to absolute V-band magnitude (Rv), but not in the ratio of the radio core to extended flux (Rc) and the Eddington ratio. Compared with NFBs, FBs have larger mean jet power, Rc and Rv, while having smaller mean redshift, black hole mass and broad-line luminosity. These results support the fact that the beaming effect is the main reason for differences between FBs and NFBs, and that FBs are likely to have a more powerful jet. For both FBs and NFBs, there are significant correlations between the jet power and the accretion rate (traced by the broad-emission line luminosity), and between the jet power and the black hole mass. For FBs, the black hole mass does not have a significant influence on jet power, while for NFBs, both the accretion rate and black hole mass contribute to the jet power. Our results support the ‘blazar sequence’ and show that the synchrotron peak frequency (νpeak) is associated with the accretion rate but not with the black hole mass.