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Related papers: General Physical Properties of CGRaBS Blazars

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Since 2002, the number of detected blazars at gamma-ray energies above 100 GeV has more than doubled. I study 17 blazars currently known to emit E>100 GeV gamma rays. Their intrinsic energy spectra are reconstructed by removing…

Astrophysics · Physics 2008-05-27 Robert Wagner

We started a follow-up investigation of the Deep X-ray Radio Blazar Survey objects with declination >-10 deg. We undertook a survey with the EVN at 5GHz to make the first images of a complete sample of weak blazars, aiming at a comparison…

Astrophysics of Galaxies · Physics 2015-04-29 F. Mantovani , M. Bondi , K. -H. Mack , W. Alef , E. Ros , J. A. Zensus

Blazars, a subset of powerful active galactic nuclei, feature relativistic jets that shine in a broadband electromagnetic radiation, e. g. from radio to TeV emission. Here I present the results of the studies that explore gamma-ray and…

High Energy Astrophysical Phenomena · Physics 2022-10-18 Gopal Bhatta

Context. Although Blazars are a small fraction of the overall AGN population they are expected to be the dominant population of extragalactic sources in the hard X-ray and gamma-ray bands and have been shown to be the largest contaminant of…

Astrophysics · Physics 2008-11-26 S. Turriziani , E. Cavazzuti , P. Giommi

Context: Being dominated by non-thermal emission from aligned relativistic jets, blazars allow us to elucidate the physics of extragalactic jets, and, ltimately, how the energy is extracted from the central black hole in radio-loud active…

We present a milliarcsecond-resolution radio survey of 17 high-redshift (4 < z < 5.4) blazar candidates observed with the European Very Long Baseline Interferometry (VLBI) Network at 5 GHz. The primary objective of this study was to…

Since 2002, the number of detected blazars at E_\gamma > 100 GeV has more than doubled. I study all currently known BL Lac-type objects with published energy spectra. Their intrinsic energy spectra are reconstructed by removing…

Astrophysics · Physics 2009-01-08 Robert Wagner

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). This large, flux-limited sample of active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 J. D. Linford , G. B. Taylor , R. Romani , S. E. Healey , J. F. Helmboldt , A. C. S. Readhead , R. Reeves , J. Richards , G. Cotter

We use 3 years of data from the Swift/BAT survey to select a complete sample of X-ray blazars above 15 keV. This sample comprises 26 Flat-Spectrum Radio Quasars (FSRQs) and 12 BL Lac objects detected over a redshift range of 0.03<z<4.0. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-04 M. Ajello , L. Costamante , R. M. Sambruna , N. Gehrels , J. Chiang , A. Rau , A. Escala , J. Greiner , J. Tueller , J. V. Wall , R. F. Mushotzky

The phenomenology of gamma-ray bright blazars can be accounted for by a sequence in the source power and intensity of the diffuse radiation field surrounding the relativistic jet. Correspondingly, the equilibrium particle distribution peaks…

Astrophysics · Physics 2009-10-30 G. Ghisellini , A. Celotti , G. Fossati , L. Maraschi , A. Comastri

We used the data from the Fermi Gamma-ray Space Telescope to characterise the {\gamma}-ray flux variability of blazars on month-like time scales. Our sample consists of 1120 blazars of which 481 are flat spectrum radio quasars (FSRQs) and…

High Energy Astrophysical Phenomena · Physics 2020-02-12 Bhoomika Rajput , C. S. Stalin , Suvendu Rakshit

We study the general physical properties of Fermi blazars using the Fermi fourth source catalog data (4FGL-DR2). The quasi-simultaneous multiwavelength data of Fermi blazar are fitted by using the one-zone leptonic model to obtain some…

High Energy Astrophysical Phenomena · Physics 2023-07-03 Yongyun Chen , Qiusheng Gu , Junhui Fan , Xiaoling Yu , Xiaogu Zhong , Hongyu Liu , Nan Ding , Dingrong Xiong , Xiaotong Guo

The most powerful sources among the blazar family are MeV blazars. Often detected at $z>2$, they usually display high X- and \gm-ray luminosities, larger-than-average jet powers and black hole masses $\gtrsim 10^9 M_{\odot}$. In the present…

High Energy Astrophysical Phenomena · Physics 2017-04-26 L. Marcotulli , V. S. Paliya , M. Ajello , A. Kaur , D. H. Hartmann , D. Gasparrini , J. Greiner , A. Rau , P. Schady , M. Balokovic , D. Stern , G. Madejski

We present the results of studying the accretion disk vs jet power for a large fraction of all the blazars detected by the Fermi Gamma-Ray Space Telescope. The disk power is inferred from the emission line luminosities obtained from…

High Energy Astrophysical Phenomena · Physics 2022-09-27 Garima Rajguru , Ritaban Chatterjee

High redshift blazars are among the most powerful non-explosive sources in the Universe and play a crucial role in understanding the evolution of relativistic jets. To understand these bright objects, we performed a detailed investigation…

High Energy Astrophysical Phenomena · Physics 2024-01-29 N. Sahakyan , G. Harutyunyan , S. Gasparyan , D. Israyelyan

Blazars constitute the most enigmatic class of extragalactic gamma-ray sources, and their observational features have been ascribed to a relativistic jet closely aligned to the line of sight. They are generally divided in two main classes:…

High Energy Astrophysical Phenomena · Physics 2015-06-04 R. D'Abrusco , F. Massaro. M. Ajello , J. E. Grindlay , H. A. Smith , G. Tosti

We present $\gamma$-ray, X-ray, ultraviolet, optical, and near-infrared light curves of 33 $\gamma$-ray bright blazars over four years that we have been monitoring since 2008 August with multiple optical, ground-based telescopes and the…

The exact location of the gamma-ray emitting region in blazars is still controversial. In order to attack this problem we present first results of a cross-correlation analysis between radio (11 cm to 0.8 mm wavelength, F-GAMMA program) and…

We describe a uniform all-sky survey of bright blazars, selected primarily by their flat radio spectra, that is designed to provide a large catalog of likely gamma-ray AGN. The defined sample has 1625 targets with radio and X-ray properties…

Our knowledge of the blazar surface densities and luminosity functions, which are fundamental parameters, relies still on samples at relatively high flux limits. As a result, our understanding of this rare class of active galactic nuclei is…

Astrophysics · Physics 2011-02-11 P. Padovani , P. Giommi , H. Landt , E. S. Perlman