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Related papers: Unifying All Blazars

200 papers

Among active galactic nuclei, BL Lac objects show extreme properties that have been interpreted as the effect of relativistic beaming on the emission from a plasma jet oriented close to the line of sight. The Doppler amplification of the…

Astrophysics of Galaxies · Physics 2015-06-29 Alessandro Capetti , Claudia M. Raiteri

We revisit the blazar sequence exploiting the complete, flux limited sample of blazars with known redshift detected by the Fermi satellite after 4 years of operations (the 3LAC sample). We divide the sources into gamma-ray luminosity bins,…

High Energy Astrophysical Phenomena · Physics 2017-05-31 G. Ghisellini , C. Righi , L. Costamante , F. Tavecchio

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

Mildly relativistic, oblique shocks are frequently invoked as possible sites of relativistic particle acceleration and production of strongly variable, polarized multi-wavelength emission from relativistic jet sources such as blazars, via…

High Energy Astrophysical Phenomena · Physics 2019-04-01 Markus Boettcher , Matthew G. Baring

Results obtained with BeppoSAX observations of blazars within various collaborative programs are presented. The spectral similarity "paradigm", whereby the spectral energy distributions of blazars follow a sequence, leading to a unified…

Astrophysics · Physics 2009-10-31 L. Maraschi , L. Chiappetti , G. Fossati , E. Pian , F. Tavecchio

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

The current status of leptonic jet models for gamma-ray blazars is reviewed. Differences between the quasar and BL-Lac subclasses of blazars may be understood in terms of the dominance of different radiation mechanisms in the gamma-ray…

Astrophysics · Physics 2009-10-31 M. Boettcher

We analyse 77 \textit{Fermi} sources and their potential low-energy counterparts previously proposed in the literature. These sources were classified as active galactic nuclei, mainly blazars, based on optical spectroscopy. The main goals…

High Energy Astrophysical Phenomena · Physics 2025-09-03 Alberto Ulgiati , Paolo Padovani , Paolo Giommi , Simona Paiano , Ciro Pinto

The extragalactic $\gamma$-ray sky is dominated by blazars and their study plays an important role in understanding jet physics, cosmic evolution history and origin of ultra high energy cosmic rays. In this work, we study a large sample of…

High Energy Astrophysical Phenomena · Physics 2022-05-23 Muhammad Shahzad Anjum , Liang Chen , Minfeng Gu

In this review, recent progress in theoretical models for the broadband (radio through gamma-ray) emission from blazars are summarized. The salient features of both leptonic and hadronic models are reviewed. I present sample modeling…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-03 Markus Boettcher

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

Extreme BL Lacs (EHBL) form a subclass of blazars which challenge standard emission scenarios. In a recent study it has been argued that their peculiar properties can be explained if emitting electrons are accelerated in a series of oblique…

High Energy Astrophysical Phenomena · Physics 2022-08-03 F. Tavecchio , A. Costa , A. Sciaccaluga

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

Extreme high-energy peaked BL Lac objects (EHBLs) are an emerging class of blazars with exceptional spectral properties. The non-thermal emission of the relativistic jet peaks in the spectral energy distribution (SED) plot with the…

High Energy Astrophysical Phenomena · Physics 2019-07-19 L. Foffano , E. Prandini , A. Franceschini , S. Paiano

Many quasi-simultaneous optical observations of 17 blazars are obtained from previous papers published over the last 19 years in order to investigate the spectral slope variability and understand the radiation mechanism of blazars. The…

Astrophysics · Physics 2019-09-04 Shao Ming Hu , G. Zhao , H. Y. Guo , X. Zhang , Y. G. Zheng

Multi-Messenger observations and theory of astrophysical objects is fast becoming a critical research area in the astrophysics scientific community. In particular, point-like objects like that of BL Lac, flat spectrum radio quasars (FSRQ),…

High Energy Astrophysical Phenomena · Physics 2024-05-24 Ronald Gamble , Jordan Forman , Amethyst Barnes , Gokul Srinivasaragavan , Isiah Holt , Marvin Jones

Our recent progress on time-dependent modeling of the multiwavelength spectra and variability of blazars with leptonic and hadronic jet models is reviewed. Special emphasis is placed on X-ray spectral variability of low-frequency peaked…

Astrophysics · Physics 2007-05-23 M. Boettcher

We use statistical results from a large sample of about 500 blazars, based on two surveys, the Deep X-ray Radio Blazar Survey (DXRBS), nearly complete, and the RASS-Green Bank survey (RGB), to provide new constraints on the spectral energy…

Astrophysics · Physics 2009-11-07 P. Padovani , E. Perlman , H. Landt , P. Giommi , M. Perri

Blazars are conventionally classified into BL Lac objects and flat-spectrum radio quasars (FSRQs), commonly associated with radiatively inefficient and efficient accretion onto supermassive black holes, respectively. Increasing evidence,…

High Energy Astrophysical Phenomena · Physics 2026-05-18 Javaid Tantry , Naseer Iqbal

As an overview of blazar research, we briefly discuss some of the themes of this conference, including the various types of blazars, blazar samples and selection effects, unified schemes, evolution, and jet physics.

Astrophysics · Physics 2007-05-23 Paolo Padovani , C. Megan Urry
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