The media of the ultra-right

Padovani, Cinzia

doi:10.1075/jlp.15.4.02pad

Cited by 23 publications

(24 citation statements)

References 11 publications

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“…Overall, we find a strong positive correlation (ρ s = 0.63 ± 0.03, PNC< 1 × 10 −5 ), which remains valid if we consider the γ-ray loud and the γ-ray quiet blazar populations separately (Table 10). However, since both L disk and P rad depend on redshift, we also perform a partial correlation test by following the prescriptions of Padovani (1992). Even after excluding the common redshift dependence, both L disk and P rad still correlate, although the significance becomes a bit weaker (ρ par = 0.19 ± 0.08, PNC< 1 × 10 −5 ).…”

Section: Accretion-jet Connection In Blazarsmentioning

confidence: 99%

General Physical Properties of CGRaBS Blazars

Paliya

Marcotulli

Ajello

et al. 2017

ApJ

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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 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 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.

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Section: Accretion-jet Connection In Blazarsmentioning

confidence: 99%

General Physical Properties of CGRaBS Blazars

Paliya

Marcotulli

Ajello

et al. 2017

ApJ

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“…A real correlation should remove the redshift effect. In doing so, we use the method by Padovani (1992). If variables i and j are correlated with the third variable k, then the correlation between i and j should exclude the effect of the third variable k. In the case of three variables i, j and k, if the correlation coefficients of the relation between any two variables are represented as r ij , r ik , r jk respectively, then the correlation coefficient r ij excluded the effect of the third variable k is represented as r ij,k = (r ij − r ik r jk )/ (1 − r 2 ik )(1 − r 2 jk ).…”

Section: Luminosity Vs Luminositymentioning

confidence: 99%

The Spectral Energy Distributions of Fermi Blazars

Jiang¹,

Yang²,

Liu³

et al. 2016

ApJS

162

180

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In this paper, multi-wavelength data are compiled for a sample of 1425 Fermi blazars to calculate their spectral energy distributions (SEDs). A parabolic function, log(νF ν ) = P 1 (logν − P 2 ) 2 + P 3 , is used for SED fitting. Synchrotron peak frequency (logν p ), spectral curvature (P 1 ), peak flux (ν p F νp ), and integrated flux (νF ν ) are successfully obtained for 1392 blazars (461 flat spectrum radio quasarsFSRQs, 620 BL Lacs-BLs and 311 blazars of uncertain type-BCUs, 999 sources have known redshifts). Monochromatic luminosity at radio 1.4 GHz, optical R band, X-ray at 1 keV and γ-ray at 1 GeV, peak luminosity, integrated luminosity and effective spectral indexes of radio to optical (α RO ), and optical to X-ray (α OX ) are calculated. The "Bayesian classification" is employed to logν p in the rest frame for 999 blazars with available redshift and the results show that 3 components are enough to fit the logν p distribution, there is no ultra high peaked subclass. Based on the 3 components, the subclasses of blazars using the acronyms of Abdo et al. (2010a) are classified, and some mutual correlations are also studied. Conclusions are finally drawn as follows: (1) SEDs are successfully obtained for 1392 blazars. The fitted peak frequencies are compared with common sources from samples available ( Sambruna et al. 1996, Nieppola et al. 2006, 2008, Abdo et al. 2010a. (2) -2 -peak sources (ISPs) if 14.0 < log ν p (Hz) ≤ 15.3, and high synchrotron peak sources (HSPs) if log ν p (Hz) > 15.3. (3) γ-ray emissions are strongly correlated with radio emissions. γ-ray luminosity is also correlated with synchrotron peak luminosity and integrated luminosity. (4) There is an anti-correlation between peak frequency and peak luminosity within the whole blazar sample. However, there is a marginally positive correlation for HBLs, and no correlations for FSRQs or LBLs. (5) There are anti-correlations between the monochromatic luminosities (γ-ray and radio bands) and the peak frequency within the whole sample and BL Lacs. (6) The optical to X-ray (α OX ) and radio to optical (α RO ) spectral indexes are strongly anti-correlated with peak frequency (log ν p ) within the whole sample, but the correlations for subclasses of FSRQs, LBLs, and HBLs are different.

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“…To avoid this, we perform a partial correlation analysis (see e.g. Padovani 1992;Ghirlanda et al 2011;Inoue 2011) to test the correlation between the logarithmic optical and radio luminosities excluding the redshift dependence. The Spearman rank correlation gives ρ or,z = 0.39 with the p-value of < 10 −10 (i.e.…”

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confidence: 99%

Disk–Jet Connection in Active Supermassive Black Holes in the Standard Accretion Disk Regime

Inoue

Doi

Tanaka

et al. 2017

ApJ

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We study the disk-jet connection in supermassive black holes by investigating the properties of their optical and radio emissions utilizing the SDSS-DR7 and the NVSS catalogs. Our sample contains 7017 radio-loud quasars with detection both at 1.4 GHz and SDSS optical spectrum. Using this radioloud quasar sample, we investigate the correlation among the jet power (P jet ), the bolometric disk luminosity (L disk ), and the black hole mass (M BH ) in the standard accretion disk regime. We find that the jet powers correlate with the bolometric disk luminosities as log P jet = (0.96 ± 0.012) log L disk + (0.79 ± 0.55). This suggests that the jet production efficiency of η jet 1.1 +2.6 −0.76 × 10 −2 assuming the disk radiative efficiency of 0.1 implying low black hole spin parameters and/or low magnetic flux for radio-loud quasars. But it can be also due to dependence of the efficiency on geometrical thickness of the accretion flow which is expected to be small for quasars accreting at the disk Eddington ratios 0.01 λ 0.3. This low jet production efficiency does not significantly increase even if we set the disk radiative efficiency of 0.3. We also investigate the fundamental plane in our samples among P jet , L disk , and M BH . We could not find a statistically significant fundamental plane for radio-loud quasars in the standard accretion regime.

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The media of the ultra-right

Cited by 23 publications

References 11 publications

General Physical Properties of CGRaBS Blazars

General Physical Properties of CGRaBS Blazars

The Spectral Energy Distributions of Fermi Blazars

Disk–Jet Connection in Active Supermassive Black Holes in the Standard Accretion Disk Regime

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