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Models of variability in blazar jets

A. Mastichiadis·J. G. Kirk
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Abstract

We present the expected variability features in the context of the Synchro- Self-Compton (SSC) model of emission from Active Galactic Nuclei (AGNs) and show that the homogeneous SSC model describes well the observed multi- wavelength spectrum and variability of objects such as Mkn 421 and Mkn 501; however in order to explain the very fast flaring timescales occasionally observed from these objects one should use a laminar, rather than spherical, source geometry. This picture leads naturally to a shock-in- jet model which we approach as a site of diffusive particle acceleration. We show that this acceleration scheme can explain certain characteristic features of AGN X-ray spectra and provides us with further observational tests.

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A. Mastichiadis, J. G. Kirk. 1999-03-18. Models of variability in blazar jets. https://arxiv.org/abs/astro-ph/9903280

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