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Related papers: Correlated Variability in Blazars

200 papers

TeV emission can be a common characteristic of low power blazars. This is in line with the sequence of blazars relating the observed bolometric luminosity with their overall spectral energy distribution. Detecting new TeV blazars, possibly…

Astrophysics · Physics 2009-11-10 G. Ghisellini

Blazars represent dominant population of the extragalactic $\gamma$-ray sources in the Universe. These sources exhibit some characteristic properties like strong and non-thermal continuum emission over the entire electromagnetic spectrum…

High Energy Astrophysical Phenomena · Physics 2020-10-07 K. K. Singh , P. J. Meintjes

We investigate the temporal variability of polarization of synchrotron radiation from blazar jets. Multiwavelength observations revealed high-amplitude rotations of the electric vector position angle (EVPA), both in the optical and in the…

High Energy Astrophysical Phenomena · Physics 2026-01-13 Filippo Bolis , Emanuele Sobacchi , Fabrizio Tavecchio

High-energy photons propagating in the magnetised medium with large velocity gradients can mediate energy and momentum exchange. Conversion of these photons into electron-positron pairs in the field of soft photons with the consequent…

Astrophysics · Physics 2008-11-26 Boris E. Stern , Juri Poutanen

Constraints on the dynamics, dissipation, and production of VHE neutrinos in relativistic jets are derived using opacity calculations and VHE $\gamma$-ray observations. In particular, it is demonstrated how rapid variability of the…

Astrophysics · Physics 2007-07-17 Amir Levinson

Blazars are characterized by relativistic jets that are closely aligned with our line of sight. This results in relativistic beaming, making blazars among the most luminous extragalactic sources across the electromagnetic spectrum, from…

High Energy Astrophysical Phenomena · Physics 2025-07-14 Stamatios Ilias Stathopoulos , Maria Petropoulou

A time-dependent emission model for blazar jets, taking acceleration due to Fermi-I and Fermi-II processes for electrons and protons as well as all relevant radiative processes self-consistently into account, is presented. The presence of…

High Energy Astrophysical Phenomena · Physics 2014-12-10 Matthias Weidinger , Felix Spanier

We will present a summary of the observations of blazars by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO). EGRET has detected high energy gamma-ray emission at energies greater than 100 MeV…

Astrophysics · Physics 2016-01-27 R. Mukherjee

In this work, a time-dependent modeling is developed to study the emission properties of blazars in the low state. Motivated by various observations, we speculate and assume that numerous discrete radiation zones throughout the jet of a…

High Energy Astrophysical Phenomena · Physics 2023-09-22 Ruo-Yu Liu , Rui Xue , Ze-Rui Wang , Hong-Bin Tan , Markus Böttcher

The multi-wavelength spectral and temporal variability observed in blazars set tight constraints on current theoretical emission models. Here, we investigate the relativistic magnetic reconnection process as a source of blazar emission in…

High Energy Astrophysical Phenomena · Physics 2018-12-04 I. M. Christie , M. Petropoulou , L. Sironi , D. Giannios

We propose a new model for the description of ultra-short flares from TeV blazars by compact magnetized condensations (blobs), produced when red giant stars cross the jet close to the central black hole. Our study includes a simple…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Maxim V. Barkov , Felix A. Aharonian , Sergey V. Bogovalov , Stanislav R. Kelner , Dmitriy V. Khangulyan

Despite their different nature and physics, blazars and gamma-ray bursts have in common very powerful relativistic jets, which make them the most luminous sources in the Universe. The energy extraction from the central compact object, the…

High Energy Astrophysical Phenomena · Physics 2015-12-15 Elena Pian

Supermassive black holes in the centers of galaxies are very common. They are known to rotate, accrete, spin down and eject highly relativistic jets; those jets pointed at us all seem to show a spectrum with two strong bumps, one in the TeV…

Astrophysics of Galaxies · Physics 2015-05-20 P. L. Biermann , J. K. Becker , L. I. Caramete , F. Fraschetti , T. Kneiske , A. Meli , T. Stanev

The extreme variability of blazars, in both timescale and amplitude, is generally explained as the effect of a relativistic jet closely aligned to the observer's line-of-sight. Due to causality arguments, variability characteristics…

Blazar emission is dominated by non-thermal radiation from a relativistic jet pointing toward us, therefore undergoing Doppler beaming. This is responsible for flux enhancement and contraction of the variability time scales, so that most…

High Energy Astrophysical Phenomena · Physics 2019-08-13 C. M. Raiteri , M. Villata

Lately a specific kind of blazars drew the attention of the gamma-ray astronomy community: the extreme TeV BL Lacs, blazars that present an extremely energetic and hard emission at very high-energy. Explaining their features is still an…

High Energy Astrophysical Phenomena · Physics 2022-10-12 Alberto Sciaccaluga , Fabrizio Tavecchio

In the first of a series of papers investigating emission from blazar jets from radio to high-energy {\gamma}-rays, we revisit the class of models where the jet has a uniform conical ballistic structure. We argue that by using simple…

High Energy Astrophysical Phenomena · Physics 2012-12-13 William J. Potter , Garret Cotter

The interaction of TeV photons from blazars with the extragalactic background light produces a relativistic beam of electron-positron pairs streaming through the intergalactic medium (IGM). The fate of the beam energy is uncertain. By means…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Lorenzo Sironi , Dimitrios Giannios

Context.Blazars, a sub-category of Active Galactic Nuclei, are characterized by their non-thermal variable emission. This emission extends over the whole electromagnetic spectrum and is a consequence of particle acceleration inside their…

High Energy Astrophysical Phenomena · Physics 2021-12-22 Stella S. Boula , Apostolos Mastichiadis

Relativistic jets are one of the most powerful manifestations of the release of energy related to the supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…

High Energy Astrophysical Phenomena · Physics 2015-04-14 M. Orienti