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Related papers: Internal Shocks and the Blazar Sequence

200 papers

In this review, recent progress in theoretical models for blazar emission will be summarized. The salient features of both leptonic and lepto-hadronic approaches to modeling blazar spectral energy distributions will be reviewed. I will…

High Energy Astrophysical Phenomena · Physics 2010-06-28 Markus Boettcher

The current status of leptonic jet models for 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 regime.…

Astrophysics · Physics 2007-05-23 M. Boettcher

The transient emission produced behind internal shocks that are driven by overtaking collisions of a magnetized, relativistic outflow is considered. A self-consistent model capable of describing the structure and dynamics of the shocks and…

Astrophysics · Physics 2009-10-30 Amir Levinson

Blazars, a highly energetic subclass of jetted active galactic nuclei, show a broad band spectral energy distribution (SED) with two bumps, resulting from non-thermal jet emission. In 1998, an anticorrelation between the SED luminosity and…

High Energy Astrophysical Phenomena · Physics 2025-06-24 I. Viale , E. Prandini , C. Righi , F. Bovolon , N. Sahakyan

The radiative loss interpretation for the broken power-law spectra of blazars is often questioned since the difference between the indices does not support this inference. Using the blazar Mkn 421 as a case study, we performed a detailed…

High Energy Astrophysical Phenomena · Physics 2022-06-22 C. Baheeja , S. Sahayanathan , Frank M. Rieger , Sitha K Jagan , C. D. Ravikumar

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

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

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

The new results of the evolution of the synchrotron peak for Mrk 421 are mostly likely related to the particle acceleration process. In order to account for the above results, we present a model of blazar variability during the flare in…

Astrophysics · Physics 2016-08-30 Jiancheng Wang , Jirong Mao

We have considered all blazars observed in the X-ray band and for which the slope of the X-ray spectrum is available. We have collected 421 spectra of 268 blazars, including 12 archival unpublished ASCA spectra of 7 blazars whose analysisis…

Astrophysics · Physics 2009-11-06 D. Donato , G. Ghisellini , G. Tagliaferri , G. Fossati

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 preliminary results of our work on blazar unification. We assume that all blazars have a broad line region (BLR) and that the size of the BLR scales with the power of the source in a manner similar to that derived through…

Astrophysics · Physics 2007-05-23 Markos Georganopoulos , John G. Kirk , Apostolos Mastichiadis

We study a sample of 30 high-redshift blazars ($z>2.5$) by means of spectra and the radiation mechanism with Fermi Large Area Telescope $\gamma$-ray observations spanning 15 years. Three models -- the power law, power law with an…

High Energy Astrophysical Phenomena · Physics 2025-01-27 Fan Wu , Benzhong Dai

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

The blazars 3C 454.3, PKS 0537-441 and PKS 2155-304 are traditionally known to be among the most active sources of this class. They emit at all frequencies, up to the gamma-rays, and are good probes of multiwavelength nuclear variability.…

Astrophysics · Physics 2007-07-25 Elena Pian , Luigi Foschini , Gabriele Ghisellini

We compute the dynamics and emission of dissipative shells that are subject to a strong Compton drag, under simplifying assumptions about the dissipation mechanism. We show that under conditions prevailing in blazars, substantial…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Omri Golan , Amir Levinson

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 are the most violent steady/recurrent sources of high-energy gamma-ray emission in the known Universe. They are prominent emitters of electromagnetic radiation throughout the entire electromagnetic spectrum. The observable radiation…

Astrophysics · Physics 2008-11-26 Markus Boettcher

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

In this paper we investigate the properties of a sample of six BL Lacs by fitting their spectra using our inhomogeneous jet model with an accelerating, magnetically dominated, parabolic base, which transitions to a slowly decelerating…

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