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Related papers: An evolutionary scenario for blazar unification

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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 $\gamma$-ray detected ($\gamma$-ray loud) and 191 non $\gamma$-ray detected…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Vaidehi S. Paliya , L. Marcotulli , M. Ajello , M. Joshi , S. Sahayanathan , A. R. Rao , D. Hartmann

The Fermi Gamma-Ray Space Telescope observations of blazars show a strong correlation between the spectral index of their gamma-ray spectra and their synchrotron peak frequency $\nu_{\rm{pk}}^{\rm{syn}}$; additionally, the rate of Compton…

High Energy Astrophysical Phenomena · Physics 2018-10-17 Stella Boula , Demosthenes Kazanas , Apostolos Mastichiadis

We analyse a group of radio sources, a subset of the 200 mJy sample, all of which have core-jet radio structures measured with VLBI and have flat spectra stretching from the radio to the millimetre/sub-millimetre band. Thus the objects have…

Astrophysics · Physics 2009-11-10 S. Anton , I. W. A. Browne

The radio-loud AGN unification model associates powerful radio galaxies with radio-loud quasars and blazars. In analogy with the radio-quiet scheme, the nuclear regions of objects showing only narrow emission lines in their optical spectrum…

Astrophysics · Physics 2017-08-23 Marco Chiaberge

Blazars are currently separated into BL Lacertae objects (BL Lacs) and flat spectrum radio quasars (FSRQ) based on the strength of their emission lines. This is done rather arbitrarily by defining a diagonal line in the Ca H&K break value…

Astrophysics · Physics 2009-11-10 H. Landt , P. Padovani , E. S. Perlman , P. Giommi

We model rapid variability of multifrequency emission from blazars occurring across the electromagnetic spectrum (from radio to gamma-rays). Lower energy emission is produced by the synchrotron mechanism, whereas higher energy emission is…

Astrophysics · Physics 2009-11-10 Andrei Sokolov , Alan P. Marscher , Ian M. McHardy

We carried out multi-color optical monitoring of a sample of ten blazars from 2005 to 2011. The sample contains 3 LBLs, 2 IBLs, 4 HBLs, and 1 FSRQ. Our monitoring focused on the long-term variability and the sample included nine BL Lac…

Astrophysics of Galaxies · Physics 2018-08-08 Nankun Meng , Xiaoyuan Zhang , Jianghua Wu , Jun Ma , Xu Zhou

Recent works have developed samples of blazars from among the Fermi-LAT unassociated sources via machine learning comparisons with known blazar samples. Continued analysis of these new blazars tests the predictions of the blazar sequence…

High Energy Astrophysical Phenomena · Physics 2023-07-17 Stephen Kerby , Abraham D. Falcone

Blazar emission models based on magnetic reconnection succeed in reproducing many observed spectral and temporal features, including the short-duration luminous flaring events. Plasmoids, a self-consistent by-product of the tearing…

High Energy Astrophysical Phenomena · Physics 2020-01-08 I. M. Christie , M. Petropoulou , L. Sironi , D. Giannios

The SEDs of 18 GeV FSRQs are collected and compiled from literature, in which both the jet emission and the accretion disk radiation can be observed, in order to investigate the correlations among their jet power (P_jet), accretion disk…

High Energy Astrophysical Phenomena · Physics 2015-04-28 Jin Zhang , Zi-Wei Xue , Jian-Jian He , En-Wei Liang , Shuang-Nan Zhang

We demonstrate that the spectral differences between Flat Spectrum Radio Quasars (FSRQ) with steep gamma-ray spectra (MeV-blazars) and FSRQ with flat gamma-ray spectra (GeV-blazars) can be explained by assuming that in the MeV-blazars, the…

Astrophysics · Physics 2007-05-23 M. Blazejowski , M. Sikora , R. Moderski , G. Madejski

The origin and evolution of spectral curvature in blazar spectral energy distribution (SED) is still unclear. Since the observed SED curvature is related to an intrinsic curvature in emitting electron energy distribution (EED), we study…

High Energy Astrophysical Phenomena · Physics 2020-07-29 Muhammad S. Anjum , Liang Chen , Minfeng Gu

The uncharted territory of the high-redshift ($z\gtrsim3$) Universe holds the key to understand the evolution of quasars. In an attempt to identify the most extreme members of the quasar population, i.e., blazars, we have carried out a…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Vaidehi S. Paliya , M. Ajello , H. -M. Cao , M. Giroletti , Amanpreet Kaur , Greg Madejski , Benoit Lott , D. Hartmann

Most of the extragalactic sources detected at TeV energies are BL Lac objects. They belong to the subclass of "high frequency peaked BL Lacs" (HBLs) exhibiting spectral energy distributions with a lower energy peak in the X-ray band; this…

High Energy Astrophysical Phenomena · Physics 2015-06-04 F. Massaro , A. Paggi , M. Elvis , A. Cavaliere

We present simultaneous Planck, Swift, Fermi, and ground-based data for 105 blazars belonging to three samples with flux limits in the soft X-ray, hard X-ray, and gamma-ray bands. Our unique data set has allowed us to demonstrate that the…

It has been inferred from large unbiased samples that $10\%$-$15\%$ of all quasars are radio-loud (RL). Using the quasar catalog from the Sloan Digital Sky Survey, we show that the radio-loud fraction (RLF) for high broad line (HBL)…

Astrophysics of Galaxies · Physics 2022-08-31 A. Chakraborty , A. Bhattacharjee , M. S. Brotherton , R. Chatterjee , S. Chatterjee , M. Gilbert

Recent multiwavelength observations of PKS 0208-512 by SMARTS, Fermi, and Swift revealed that gamma-ray and optical light curves of this flat spectrum radio quasars are highly correlated, but with an exception of one large optical flare…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Xuhui Chen , Ritaban Chatterjee , Giovanni Fossati , Martin Pohl

We revisit the so called "blazar sequence", which connects the observed bolometric luminosity to the shape of the spectral energy distribution (SED) of blazars. We propose that the power of the jet and the SED of its emission are linked to…

Astrophysics · Physics 2009-11-13 G. Ghisellini , F. Tavecchio

We revisit the concept of a blazar sequence that relates the synchrotron peak frequency ({\nu}peak) in blazars with synchrotron peak luminosity (Lpeak, in {\nu}L{\nu}) using a large sample of radio-loud AGN. We present observational…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-10 Eileen T. Meyer , Giovanni Fossati , Markos Georganopoulos , Matthew L. Lister

We study the quasi-simultaneous Spectral Energy Distributions (SED) of 48 LBAS blazars, collected within three months of the Fermi LAT Bright AGN Sample (LBAS) data taking period, combining Fermi and Swift data with radio NIR-Optical and…

High Energy Astrophysical Phenomena · Physics 2009-12-21 S. Raino' , E. Cavazzuti , S. Colafrancesco , P. Giommi , A. Tramacere , the Fermi-LAT Collaboration