Implications on the blazar sequence and inverse Compton models from Fermi bright blazars

Abstract

In this paper, we use the quasi-simultaneous spectra of Fermi bright blazars and Fermi detected narrow line Seyfert 1 (NLS1) to study the blazar sequence and inverse Compton (IC) models. I. The synchrotron peak luminosities (L_{s}) significantly inverse correlate with the synchrotron peak frequencies (ν_{s}), L_{s}\proptoν_{s}^{-0.44}, which is consistent with the blazar sequence. In addition to the correlation, there are some blazars showing low ν_{s} and low L_{s}. To study the relation between these low ν_{s} low L_{s} blazars and the blazar sequence, we present correlations of the parameter L_{s}ν_{s}^{1/4} with the ratio of Compton to synchrotron peak frequencies (r_{Cs}\equivν_{C}/ν_{s}) and with the ratio of Compton to synchrotron luminosities (CD\equiv L_{C}/L_{s}). The results indicate that both correlations are significant with a Pearson's probability for null correlation of p=0.0218 and p=0.0286 respectively. This does not support the idea that the low ν_{s} low L_{s} blazars are sources with less beaming. Another possibility, as suggested by Ghisellini & Tavecchio, is that these blazars have relative lower black hole masses. To test this, we collect the black hole masses of 30 blazars from archives, and find that the hole mass correlates with the parameter L_{s}ν_{s}^{0.44} (p=0.0344). Therefore, the black hole masses of low ν_{s} low L_{s} blazars are statistically small. The NLS1s are thought to have lower black hole masses. We find that the four NLS1s detected by Fermi have low ν_{s} and low L_{s}. This supports the above result. II. The ratio r_{Cs} correlates with CD significantly (p=0.00375). The external Compton (EC) model can naturally explain this correlation, while synchrotron self Compton (SSC) model can not. This agrees with the findings of many authors that the EC process dominates the gamma-ray emission of Flat Spectrum Radio Quasars.

9 figures, accepted by ApJ

References in corpus (12)

• The power of blazar jets
• Bright AGN Source List from the First Three Months of the Fermi Large Area Telescope All-Sky Survey
• The blazar sequence: a new perspective
• A Population of Radio-loud Narrow Line Seyfert 1 Galaxies with Blazar-like Properties?
• The Blazar Sequence: Validity and Predictions
• Geometry and inclination of the broad line region in blazars
• Synoptic studies of seventeen blazars detected in very high-energy gamma-rays
• On the BL Lacertae objects/radio quasars and the FRI/II dichotomy
• A test on external Compton models for $\gamma$-ray active galactic nuclei
• Models for the Spectral Energy Distributions and Variability of Blazars
• The Spectral Sequence of Blazars - Status and Perspectives
• SDSS spectroscopy for blazars in the $Fermi$ LAT bright AGN sample

Cited by in corpus (30)

• The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• Compton Dominance and the Blazar Sequence
• On the jet properties of the gamma-ray loud active galactic nuclei
• Constraints on minimum electron Lorentz factor and matter content of jets for a sample of bright Fermi blazars
• The curvature of spectral energy distribution of blazars
• Evaluating the optical classification of Fermi BCUs using machine learning
• The Nature of gamma-ray Loud Narrow Line Seyfert I Galaxies PKS 1502+036 and PKS 2004-447
• Basic properties of Fermi blazars and the "blazar sequence"
• Blazar Anti-Sequence of Spectral Variation within individual Blazars: Cases for Mrk 501 and 3C 279
• On the origin of the soft photons of the high synchrotron peaked blazar : PKS 1424+240
• The Intrinsic Properties of Multiwavelength Energy Spectra for Fermi Teraelectronvolt Blazars
• The central engines of two unusual radio-intermediate/quiet active galactic nuclei: III Zw 2 and PG 1407+265
• The Radio/Gamma Connection of Blazars from High to Low Radio Frequencies
• Evaluating the classification of Fermi BCUs from the 4FGL Catalog Using Machine Learning
• Why are some BL Lacs detected by \fermi, but others not ?
• Constraints on the location of $\gamma$-ray emitting region for a sample of blazars with radio core-shift measurements
• Gamma-ray Loudness, Synchrotron Peak Frequency, and Parsec-Scale Properties of Blazars Detected by the Fermi Large Area Telescope
• On the Origin and Evolution of Curvature of the Spectral Energy Distribution of Fermi Bright Blazars
• Constraints on the location of the gamma-ray emission region for the gamma-ray-loud radio source GB 1310+487
• Optical and Gamma-Ray Variability Behaviors of 3C 454.3 from 2006 to 2011
• What determines the observational differences of blazars?
• X-ray spectral variations of synchrotron peak in BL Lacs
• The Fermi-LAT view of the changing-look blazar OQ 334
• From the Fermi blazar sequence to the relation between Fermi blazars and gamma-ray Narrow-line Seyfert 1 Galaxies
• A γ-ray emitting NLS1 galaxy SDSS J095909.51+460014.3 identified by multiwavelength contemporaneous brightening
• Using the Markov Chain Monte Carlo method to study the physical properties GeV-TeV BL Lac objects
• The Connection between Radio and Gamma Ray Emission in Fermi/LAT Blazars
• Blazar Anti-Sequence of Spectral Variability for Individual TeV Blazars
• Modeling Fermi Large Area Telescope and Multiwavelength Data from Blazars
• A Physical Model for the Revised Blazar Sequence