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Related papers: Gamma-ray Clues to the Relativistic Jet Dichotomy

200 papers

Among the blazars detected by the Fermi satellite, we have selected the 23 blazars that in the three months of survey had an average gamma-ray luminosity above 1e48 erg/s. For 17 out of the 23 sources we found and analysed X-ray and…

High Energy Astrophysical Phenomena · Physics 2015-05-13 G. Ghisellini , F. Tavecchio , G. Ghirlanda

Both leptonic and hadronic emission processes may contribute to blazar jet emission; which dominates in blazars's high energy emission component remains an open question. Some intermediate synchrotron peaked blazars transition from their…

High Energy Astrophysical Phenomena · Physics 2022-06-01 Abel L. Peirson , Ioannis Liodakis , Roger W. Romani

We collect a sample of 78 Fermi detected blazars with broad line region (BLR) data and the quasi-simultaneous multi-wave band data. By analyzing the sample, we find: (1) For whole blazar sample, there exist significant correlations between…

High Energy Astrophysical Phenomena · Physics 2017-09-20 Zerui Wang , Rui Xue , Zhaohua Xie , Leiming Du , Tingfeng Yi , Yunbing Xu , Wenguang Liu

We construct a large sample of gamma-ray blazars with low-frequency radio data using the recent released TGSS AD1 catalog at 150 MHz. The radio/gamma connections of blazars are compared from 143 GHz to 150 MHz. The radio flux density at all…

High Energy Astrophysical Phenomena · Physics 2018-12-26 Xu-Liang Fan , Qingwen Wu

We investigate the production of gamma-rays in the inverse Compton (IC) scattering process by leptons accelerated inside relativistic blobs in jets of active galactic nuclei. Leptons are injected homogeneously inside the spherical blob and…

Astrophysics · Physics 2008-11-26 Julian Sitarek , Wlodek Bednarek

Blazars are the brightest and most abundant persistent sources in the extragalactic gamma-ray sky. Due to their significance, they are often observed across various energy bands to explore potential correlations between emissions at…

High Energy Astrophysical Phenomena · Physics 2024-01-22 P. Giommi , N. Sahakyan , D. Israyelyan , M. Manvelyan

The gamma-ray emission in broad-line blazars is generally explained as inverse Compton (IC) radiation of relativistic electrons in the jet scattering optical-UV photons from the Broad Line Region (BLR), the so-called BLR External Compton…

High Energy Astrophysical Phenomena · Physics 2018-05-16 L. Costamante , S. Cutini , G. Tosti , E. Antolini , A. Tramacere

Blazars can be divided into two sub-classes namely high energy and low energy peaked blazars. In spectral energy distribution, the first synchrotron hump of the former class peaks in UV/X-rays and in IR/optical bands for the latter class.…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Alok C. Gupta , Nibedita Kalita , Haritma Gaur , Kalpana Duorah

The multiwavelength spectra of blazars appear to be dominated by nonthermal emission from a relativistic jet oriented close to the line of sight. The recent detection of many blazars at gamma-ray energies strongly supports this scenario.…

Astrophysics · Physics 2009-10-30 C. Megan Urry

The correlation often observed in blazars between optical-to-radio outbursts and gamma-ray flares suggests that the high-energy emission region shall be co-spatial with the radio knots, several parsecs away from the central engine. This…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Marc Türler , Claes-Ingvar Björnsson

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 investigate the spectral and timing signatures of the internal-shock model for blazars. For this purpose, we develop a semi-analytical model for the time-dependent radiative output from internal shocks arising from colliding relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Markus Boettcher , Charles D. Dermer

A model is developed for the time dependent electromagnetic - radio to gamma-ray - emission of active galactic nuclei, specifically, the blazars, based on the acceleration and creation of leptons at a propagating discontinuity or {\it…

Astrophysics · Physics 2008-02-03 M. M. Romanova , R. V. E. Lovelace

Beaming effect is important for the observational properties of blazars. In this work, we collect 91 $Fermi$ blazars with available radio Doppler factors. $\gamma$-ray Doppler factors are estimated and compared with radio Doppler factors…

High Energy Astrophysical Phenomena · Physics 2017-07-19 C. Lin , J. H. Fan , H. B. Xiao

We examine a systematic comparison of jet-knots, hotspots and radio lobes recently observed with Chandra and ASCA. This report will discuss the origin of their X-ray emissions and investigate the dynamics of the jets. The data was compiled…

Astrophysics · Physics 2009-11-10 Jun Kataoka , Lukasz Stawarz

In this paper we develop the jet model of Potter & Cotter (2012) to include a magnetically dominated accelerating parabolic base transitioning to a slowly decelerating conical jet with a geometry set by recent radio observations of M87. We…

High Energy Astrophysical Phenomena · Physics 2015-06-12 William J. Potter , Garret Cotter

By considering a small sample of core-dominated radio-loud quasars with X-ray jets, I show, as has been argued previously by others, that the observations require bulk jet deceleration if all of the X-ray emission is to be explained using…

Astrophysics · Physics 2009-11-13 M. J. Hardcastle

The jets of powerful blazars propagate within regions relatively dense of radiation produced externally to the jet. This radiation is a key ingredient to understand the origin of the high energy emission of blazars, from the X-ray to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 G. Ghisellini , F. Tavecchio

The radiation observed by blazars is believed to originate from the transformation of bulk kinetic energy of relativistic jets into random energy. A simple way to achieve this is to have an intermittent central power source, producing…

Astrophysics · Physics 2007-05-23 Gabriele Ghisellini

I study the location of the $\gamma$-ray emission in blazar jets by creating a Compton-scattering approximation valid for all anisotropic radiation fields in the Thomson through Klein-Nishina regimes, which is highly accurate and can speed…

High Energy Astrophysical Phenomena · Physics 2020-03-04 Justin D. Finke