Classification and Jet Power of Fermi Blazars

Abstract

In this work, we compile a sample of 449 Fermi blazars with the luminosity of the broadline region, the black hole mass, the beam radio luminosity, and the jet power; obtain the beam power and the black hole spin; investigate the dividing line between BL Lacertae objects (BL Lacs) and flat-spectrum radio quasars (FSRQs) to identify the discrepancies in their dominant mechanisms; and revisit the dependence of the jet power on the disk accretion luminosity, the black hole mass, and the black hole spin. We come to the following conclusions. (1) A boundary of log (L BLR/L Edd) = −3.14, separating the BL Lacs and the FSRQs, is obtained from the Bayesian analysis, which is consistent with the results from the literature. We employ the boundary to divide the blazar candidates of uncertain types into candidates for BL Lacs or FSRQs, and we find five changing-look blazars at the same time. (2) A strong correlation is found between black hole mass and intrinsic γ-ray luminosity, but a weaker correlation is found between black hole mass and observed γ-ray luminosity. The latter is weakened by jet effects: it is apparently weak for BL Lacs that have disordered amplification of the Doppler factor, since their mechanism is dominated by jets, while it is moderate for FSRQs, since their mechanism is dominated by accretion processes. (3) The jets of both FSRQs and BL Lacs are likely governed by the Blandford–Znajek mechanism.

General Physical Properties of Fermi Blazars

“…There is evidence that there is a close relationship between the jet and accretion in jetted AGNs (e.g., Rawlings & Saunders 1991;Falcke & Biermann 1995;Cao & Jiang 1999;Wang et al 2004;Liu et al 2006;Gu et al 2009;Ghisellini et al 2009Ghisellini et al , 2010Ghisellini et al , 2011Sbarrato et al 2012;Ghisellini et al 2014;Sbarrato et al 2014;Xiong & Zhang 2014;Chen et al 2015b;Zhang et al 2015;Paliya et al 2017Paliya et al , 2019Chen et al 2022;Xiao et al 2022;Zhang et al 2022). Ghisellini et al (2014) used the one-zone lepton model to fit the multiband data of 217 Fermi blazars to obtain the jet power.…”

“…They suggested that the BZ mechanism may dominate over the BP mechanism in these radio-loud AGNs. Zhang et al (2022) proposed that the jets of both FSRQs and BL Lacs are likely produced by the BZ mechanism. Foschini (2011) compared the maximum jet power of the BZ mechanism with the observed jet power and suggested that the jets of FSRQs cannot be fully explained by the BZ mechanism.…”

A Study of Broad Emission Line and Doppler Factor Estimation for Fermi Blazars

“…Our sample consists of two parts: one part is from the literature (Paliya et al 2021;Zhang et al 2022), and the optical spectroscopic information of Fermi blazars is systematically compiled by Paliya et al (2021) and Zhang et al (2022) (2021) and references therein. Notably, 4FGL-DR4 is the latest incremental version released in 2023 late July, covering the last 14 yr of survey data.…”

“…Notably, 4FGL-DR4 is the latest incremental version released in 2023 late July, covering the last 14 yr of survey data. Therefore, we only considered the blazars present in the 4FGL-DR4 catalog for sources in those works (Paliya et al 2021;Zhang et al 2022). There are 608 and 408 sources with available BLR luminosities in the work of Paliya et al (2021) and Zhang et al (2022), respectively.…”

Characterizing the Emission Region Properties of Blazars

“…The jet is so powerful that it dominates the entire emission of radio-loud AGNs, but the mechanism of jet launching is still controversial. Blandford et al (1977) suggested that the jet is powered by extracting the rotational energy of the BH (the B-Z process), while Blandford & Payne (1982) suggested that the jet is powered by the rotational energy of the accretion disk (the B-P process; see also Xiong & Zhang 2014;Xiao et al 2022b;Zhang et al 2022).…”