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Related papers: Blazar sequence - an artefact of Doppler boosting

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We compile from literature the broadband SEDs of twelve TeV blazars observed simultaneously or quasi-simultaneously with Fermi/LAT and other instruments. Two SEDs are available for each of the objects and the state is identified as a low or…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jin Zhang , Shuang-Nan Zhang , En-Wei Liang

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

Blazars are among the most powerful extragalactic objects, as a sub-class of active galactic nuclei. They launch relativistic jets and their emitted radiation shows strong variability across the entire electro-magnetic spectrum. The…

High Energy Astrophysical Phenomena · Physics 2015-08-12 C. M. Fromm , L. Fuhrmann , M. Perucho

We present the results of our study of spectral energy distributions (SEDs) of a sample of ten low- to intermediate-synchrotron-peaked blazars. We investigate some of the physical parameters most likely responsible for the observed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Bindu Rani , Alok C. Gupta , R. Bachev , A. Strigachev , E. Semkov , F. D'Ammando , P. J. Wiita , M. A. Gurwell , E. Ovcharov , B. Mihov , S. Boeva , S. Peneva

Relativistic effects dominate the emission of blazar jets complicating our understanding of their intrinsic properties. Although many methods have been proposed to account for them, the variability Doppler factor method has been shown to…

High Energy Astrophysical Phenomena · Physics 2018-10-31 I. Liodakis , T. Hovatta , D. Huppenkothen , S. Kiehlmann , W. Max-Moerbeck , A. C. S. Readhead

Blazars are a subclass of radio-loud active galactic nuclei (AGNs), where the jet is aligned close to the line of sight. Blazars emission is dominated by non-thermal processes, where Doppler boosted radiation originates from a relativistic…

High Energy Astrophysical Phenomena · Physics 2021-08-19 Jakub Juryšek , Vitalii Sliusar , Dimitri Moulin , Roland Walter

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

Cosmology and Nongalactic Astrophysics · Physics 2018-07-11 Paolo Giommi , Paolo Padovani

The SED of blazars show significant curvature. In this paper, we study the curvature properties for a large sample of Fermi/LAT bright blazars based on quasi-simultaneous SED. Both SEDs of synchrotron and inverse Compton (IC) components are…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Liang Chen

The "blazar sequence" posits that the most powerful BL Lacertae objects and flat-spectrum radio quasars should have relatively small synchrotron peak frequencies, nu_peak, and that the least powerful such objects should have the highest…

Astrophysics · Physics 2008-11-26 P. Padovani

Blazar spectra are one of the most important windows into the physical processes occurring along jets. The spectrum, composed from the different emitting regions along the jet, allows us to constrain the physical conditions in the jet. I…

High Energy Astrophysical Phenomena · Physics 2015-06-17 William J. Potter , Garret Cotter

Blazars are characterized by large amplitude and fast variability, indicating that the electron distribution is rapidly changing, often on time scales shorter than the light crossing time. The emitting region is sufficiently compact to let…

Astrophysics · Physics 2009-10-31 Marco Chiaberge , Gabriele Ghisellini

The spectra of blazars form a sequence which can be parametrized in term of their observed bolometric luminosity. At the most powerful extreme of the sequence we find objects whose jet power can rival the power extracted by accretion, while…

Astrophysics · Physics 2007-05-23 G. Ghisellini

The jet properties of Mrk 501 and 3C 279 are derived by fitting the broadband spectral energy distributions with the lepton models. The derived gamma_b (the break Lorenz factor of the electron distribution) are 10^4-10^6 for Mrk 501 and…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Jin Zhang , Shuang-Nan Zhang , En-Wei Liang

The high frequency component in blazars is thought to be due to inverse Compton scattered radiation. Recent observations by Fermi-LAT are used to evaluate the details of the scattering process. A comparison is made between the usually…

High Energy Astrophysical Phenomena · Physics 2015-05-19 C. -I. Björnsson

The mechanism for producing gamma-ray quasi-periodic oscillation (QPO) in blazar is unknown. One possibility is the geometric model, in which without the need for intrinsic quasi-periodic variation, the relativistic Doppler factor changes…

High Energy Astrophysical Phenomena · Physics 2018-11-07 Dahai Yan , Jianeng Zhou , Pengfei Zhang , Qianqian Zhu , Jiancheng Wang

Blazars are characterized by large amplitude and fast variability, indicating that the electron distribution is rapidly changing, often on time scales shorter than the light crossing time. We study the time dependent behavior of the…

Astrophysics · Physics 2007-05-23 Marco Chiaberge , Gabriele Ghisellini

Blazars are a subclass of active galactic nuclei (AGNs) with extreme observation properties, which is caused by the beaming effect, expressed by a Doppler factor, in a relativistic jet. Doppler factor is an important parameter in the…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Zhiyuan Pei , Junhui Fan , Jianghe Yang , Denis Bastieri

Blazars exhibit multiwavelength variability, a phenomenon whose underlying mechanisms remain elusive. This study investigates the origin of such variability through leptonic blazar emission simulations, focusing on stochastic fluctuations…

High Energy Astrophysical Phenomena · Physics 2024-09-10 Hannes Thiersen , Michael Zacharias , Markus Böttcher

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