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Related papers: Unification of all Blazars

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Statistical analyses are invaluable methods used to understand intrinsic emission processes and the unification of extragalactic radio sources. In this paper, we collected radio, X-ray and {\gamma}-ray data of blazars from the Fermi-LAT and…

High Energy Astrophysical Phenomena · Physics 2021-12-08 E. U. Iyida , I. O. Eya , F. C. Odo

Blazars represent dominant population of the extragalactic $\gamma$-ray sources in the Universe. These sources exhibit some characteristic properties like strong and non-thermal continuum emission over the entire electromagnetic spectrum…

High Energy Astrophysical Phenomena · Physics 2020-10-07 K. K. Singh , P. J. Meintjes

The most powerful blazars are the flat spectrum radio quasars whose emission is dominated by a Compton component peaking between a few hundred keV and a few hundred MeV. We selected two bright blazars, PKS 2149-306 at redshift z=2.345 and…

Many blazars detected by the Fermi satellite, observed spectroscopically in the optical, are line-less, and have been classified as BL Lac objects. Optical-UV photometry of nearly one hundred of them allowed to determine the redshift for a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 G. Ghisellini , F. Tavecchio , L. Foschini , T. Sbarrato , G. Ghirlanda , L. Maraschi

With the arrival of powerful, ground-based gamma-ray detectors, we can now begin to seriously probe, via simultaneous X-ray/TeV observations, the origin of the gamma-ray emission in the blazars Mrk 421 and 501. If the synchrotron-Compton…

Astrophysics · Physics 2011-04-15 Paolo S. Coppi Felix A. Aharonian

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

Blazars research is one of the hot topics of contemporary extra-galactic astrophysics. That is because these sources are the most abundant type of extra-galactic gamma-ray sources and are suspected to play a central role in multi-messenger…

Extreme high-synchrotron-peak blazars (EHSPs) are postulated as the most efficient and extreme particle accelerators in the universe but remain enigmatic as a possible new class of TeV gamma-ray blazars. Blazars are active galactic nuclei…

High Energy Astrophysical Phenomena · Physics 2023-09-22 Deivid Ribeiro

The synchrotron reflection scenario recently proposed to explain $\gamma$-ray flares observed from blazar jets is studied. Our analysis takes into account the angular distribution of the beamed radiation, the finite extent of the scattering…

Astrophysics · Physics 2016-11-23 M. Boettcher , C. D. Dermer

The emission mechanisms of the blazar 3C 279 are studied by solving the kinetic equations of electrons and photons in a relativistically moving blob. The gamma-ray spectral energy distribution (SED) is fitted by inverse Compton scattering…

Astrophysics · Physics 2009-11-10 Masaaki Kusunose , Fumio Takahara , Tomohiro Kato

I discuss the spectral energy distribution (SED) of all blazars with redshift detected by the {\it Fermi} satellite and listed in the 3LAC catalog. I will update the so called "blazar sequence" from the phenomenological point of view, with…

High Energy Astrophysical Phenomena · Physics 2016-09-28 Gabriele Ghisellini

The studies and constraints on the emission region are crucial to the blazar radiation mechanism. Yet the previous works mainly focus on individual sources. In this work, we make use of the largest and the latest spectral energy…

High Energy Astrophysical Phenomena · Physics 2023-07-17 Junhui Fan , Hubing Xiao , Wenxin Yang , Lixia Zhang , Anton A. Strigachev , Rumen S. Bachev , Jianghe Yang

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

Many luminous blazars which are associated with quasar-type active galactic nuclei display broad-band spectra characterized by a large luminosity ratio of their high-energy (gamma-ray) and low-energy (synchrotron) spectral components. This…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-02 Marek Sikora , Lukasz Stawarz , Rafal Moderski , Krzysztof Nalewajko , Greg Madejski

We present a comprehensive temporal and spectral analysis of a few blazars using multi-wavelength observations. Rapid flux variations are quantified via the doubling/halving timescale method, revealing the shortest variability timescales of…

High Energy Astrophysical Phenomena · Physics 2025-06-17 Ajay Sharma , Aishwarya Sarath , Sakshi Chaudhary , Debanjan Bose

When very high-energy photons (VHE, E>100 GeV) propagate over cosmological distances, they interact with background light by pair production. Observations of spectral features in the VHE band of extragalactic sources related to this…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Matthias Lorentz , Pierre Brun , David Sanchez

We present the X-ray analysis of the largest flux-limited complete sample of blazar candidates at z>4 selected from the Cosmic Lens All Sky Survey (CLASS). After obtaining a nearly complete (24/25) X-ray coverage of the sample (from…

Astrophysics of Galaxies · Physics 2019-09-25 L. Ighina , A. Caccianiga , A. Moretti , S. Belladitta , R. Della Ceca , L. Ballo , D. Dallacasa

The H.E.S.S. collaboration recently performed the accurate measurements of the gamma-ray spectra above 200 GeV for two BL Lac-type AGN in the Southern sky: PKS 2155-304 and PKS 2005-489. The TeV spectrum of the BL Lac object 1ES 2344+514…

Astrophysics · Physics 2007-05-23 A. Konopelko , A. Mastichiadis , F. W. Stecker

Recent gamma-ray observations of the blazar 1ES 1101-232 (redshift z=0.186) reveal that the unabsorbed TeV spectrum is hard, with spectral index $\alpha \lesssim 0.5$ [$F(\nu) \propto \nu^{-\alpha}$]. We show that simple one-zone…

Astrophysics · Physics 2009-11-11 K. Katarzynski , G. Ghisellini , F. Tavecchio , J. Gracia , L. Maraschi

We have recently proposed a new simplified scenario where blazars are classified as flat-spectrum radio quasars (FSRQs) or BL Lacs according to the prescriptions of unified schemes, and to a varying combination of Doppler boosted radiation…

High Energy Astrophysical Phenomena · Physics 2015-06-15 P. Giommi , P. Padovani , G. Polenta
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