General Physical Properties of CGRaBS Blazars

Abstract

We present the results of a multi-frequency, time-averaged analysis of blazars included in the Candidate Gamma-ray Blazar Survey catalog. Our sample consists of 324 $γ$-ray detected ($γ$-ray loud) and 191 non $γ$-ray detected ($γ$-ray quiet) blazars, and we consider all the data up to 2016 April 1. We find that both the $γ$-ray loud and the $γ$-ray quiet blazar populations occupy similar regions in the WISE color-color diagram, and in the radio and X-ray bands $γ$-ray loud sources are brighter. A simple one-zone synchrotron inverse-Compton emission model is applied to derive the physical properties of both populations. We find that the central black hole mass and the accretion disk luminosity ($L_{\rm disk}$) computed from the modeling of the optical-UV emission with a Shakura-Sunyaev disk reasonably matches with that estimated from the optical spectroscopic emission-line information. A significantly larger Doppler boosting in the $γ$-ray loud blazars is noted, and their jets are more radiatively efficient. On the other hand, the $γ$-ray quiet objects are more MeV-peaked, thus could be potential targets for next-generation MeV missions. Our results confirm the earlier findings about the accretion-jet connection in blazars; however, many of the $γ$-ray quiet blazars tend to deviate from the recent claim that the jet power exceeds $L_{\rm disk}$ in blazars. A broadband study, considering a larger set of $γ$-ray quiet objects and also including BL Lacs, will be needed to confirm/reject this hypothesis and also to verify the evolution of the powerful high-redshift blazars into their low-power nearby counterparts.

28 pages, 16 figures, 10 tables. To appear in the Astrophysical journal. Full tables and figures will be available with the published version