English
Related papers

Related papers: Rapid variability in the synchrotron self Compton …

200 papers

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 consider particle acceleration to high energy via diffusive shock acceleration in a simple, self-consistent shock in jet model for blazars. Electrons are assumed to be accelerated at a shock front in relativistic jets and radiate…

Astrophysics · Physics 2007-05-23 F. M. Rieger , J. G. Kirk , A. Mastichiadis

Motivated by recent reports of strongly correlated radio and X-ray variability in 3C279 (Grandi, etal 1995), we have computed the relative amplitudes of variations in the synchrotron flux at $\nu$ and the self-Compton X-ray flux at 1 keV…

Astrophysics · Physics 2009-10-28 Mark W. Sincell

BL Lacertae objects are extreme extragalactic sources characterized by the emission of strong and rapidly variable nonthermal radiation over the entire electromagnetic spectrum. Synchrotron emission followed by inverse Compton scattering in…

Astrophysics · Physics 2009-10-31 P. Giommi , G. Ghisellini , P. Padovani , G. Tagliaferri

We study the time dependent spectra produced via the bulk Compton process by a cold, relativistic shell of plasma moving (and accelerating) along the jet of a blazar, scattering on external photons emitted by the accretion disc and…

Astrophysics · Physics 2008-11-26 Annalisa Celotti , Gabriele Ghisellini , Andrew C. Fabian

Electromagnetic radiation from blazar jets often displays strong variability, extending from radio to $\gamma$-ray frequencies. In a few cases, this variability has been characterized using Fourier time lags, such as those detected in the…

High Energy Astrophysical Phenomena · Physics 2016-06-29 Tiffany R. Lewis , Peter A. Becker , Justin D. Finke

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

This paper presents a detailed analysis of the temporal and spectral variability of the low-energy peaked BL Lac object S5 0716+714 with a long (~74 ks)X-ray observation performed by XMM-Newton on 2007 September 24-25. The source…

High Energy Astrophysical Phenomena · Physics 2015-05-18 You-Hong Zhang

We present an ordinary case in the momentum diffusion equation for the electron spectrum evolution and investigate the energy spectra and time dependent properties of flare in Mrk 421 in the frame of a time-dependent one-zone synchrotron…

High Energy Astrophysical Phenomena · Physics 2016-08-02 Y. G. Zheng , S. J. Kang , J. Li

Among active galactic nuclei, blazars show extreme variability properties. We here investigate the case of the BL Lac object S4 0954+65 with data acquired in 2019-2020 by the Transiting Exoplanet Survey Satellite (TESS) and by the Whole…

High Energy Astrophysical Phenomena · Physics 2021-05-12 C. M. Raiteri , M. Villata , V. M. Larionov , S. G. Jorstad , A. P. Marscher , Z. R. Weaver

We have studied the quasi-simultaneous Spectral Energy Distributions (SED) of 48 LBAS blazars, detected within the three months of the LAT Bright AGN Sample (LBAS) data taking period, combining Fermi and Swift data with radio NIR-Optical…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 A. Tramacere , E. Cavazzuti , P. Giommi , N. Mazziotta , C. Monte

A time-dependent Synchrotron Self Compton model (SSC) which is able to motivate the used electron spectra of many SSC models as a balance of acceleration and radiative losses is introduced. Using stochastic acceleration as well as Fermi-I…

High Energy Astrophysical Phenomena · Physics 2010-08-02 Matthias Weidinger , Felix Spanier

We analyse the influence of the stochastic particle acceleration for the evolution of the electron spectrum. We assume that all investigated spectra are generated inside a spherical, homogeneous source and also analyse the synchrotron and…

Astrophysics · Physics 2009-11-11 K. Katarzynski , G. Ghisellini , A. Mastichiadis , F. Tavecchio , L. Maraschi

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

The synchrotron emission observed from many astrophysical objects is commonly modelled to arise from relativistic electrons in an emission region occupied by a spatially homogeneous, but tangled magnetic field. However, we know that…

Astrophysics · Physics 2009-11-10 Christian R. Kaiser

The synchrotron reflection scenario recently proposed to explain $\gamma$-ray flares observed from blazar jets is studied. Our analysis takes into account the angular distribution of the beamed radiation, the finite extent of the scattering…

Astrophysics · Physics 2016-11-23 M. Boettcher , C. D. Dermer

Blazars are classified into high, intermediate and low energy peaked sources based on the location of their synchrotron peak. This lies in infra-red/optical to ultra-violet bands for low and intermediate peaked blazars. The transition from…

High Energy Astrophysical Phenomena · Physics 2017-12-06 Haritma Gaur , P. Mohan , Alicja Wierzcholska , Minfeng Gu

The overall spectra (SED) of blazars, from radio to gamma-ray energies, seem to obey well defined trends, with a continuity of properties between blazars of different classes. To quantify this statement we can either investigate their…

Astrophysics · Physics 2007-05-23 Gabriele Ghisellini

We examine the applicability of the stochastic electron acceleration to two high synchrotron peaked blazars, Mrk 421 and Mrk 501, assuming synchrotron self-Compton emission of gamma-rays. Our model considers an emitting region moving at…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Jun Kakuwa , Kenji Toma , Katsuaki Asano , Masaaki Kusunose , Fumio Takahara

We study the quasi-simultaneous Spectral Energy Distributions (SED) of 48 LBAS blazars, collected within three months of the Fermi LAT Bright AGN Sample (LBAS) data taking period, combining Fermi and Swift data with radio NIR-Optical and…

High Energy Astrophysical Phenomena · Physics 2009-12-21 S. Raino' , E. Cavazzuti , S. Colafrancesco , P. Giommi , A. Tramacere , the Fermi-LAT Collaboration