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X-ray Variability of Blazars

Published online by Cambridge University Press:  05 March 2013

Elena Pian
Elena Pian*
Affiliation:
INAF, Astronomical Observatory of Trieste, Via G. B. Tiepolo 11, I-34131 Trieste, Italy; pian@ts.astro.it
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Abstract

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Critical progress in our understanding of high energy emission from AGN has been determined in the last 10 years by X-ray monitoring campaigns with many space missions, notably ROSAT, ASCA, RXTE, BeppoSAX, and XMM, often in conjunction with observations at other frequencies. The emphasis of the present review is on recent findings about X-ray variability of blazars. Among AGN, these exhibit the largest amplitude variations of the X-ray emission, often well correlated with variations at higher energies (GeV and TeV radiation). The accurate sampling of the X-ray spectra over more than three decades in energy, made possible by the wide energy range of BeppoSAX, has also shown strong spectral variability in blazar active states, suggesting extreme electron energies and leading to the identification of a class of ‘extreme synchrotron’ sources.

Keywords

radiation mechanisms: non-thermalX-rays: galaxies
Type
Research Article
Information
Publications of the Astronomical Society of Australia , Volume 19 , Issue 1 , 2002 , pp. 49 - 54
Copyright
Copyright © Astronomical Society of Australia 2002

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