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The complex X-ray spectra of active galaxies with warm absorbers

Stefanie Komossa
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Abstract

Warm absorbers are an important new probe of the central regions of active galaxies. So far, they revealed their existence mainly in the soft X-ray spectral region. In observing and modeling this component, we can learn a lot about the nature of the warm absorber itself, its relation to other components of the active nucleus, and the intrinsic AGN X-ray spectral shape. Here, we briefly review the basic X-ray spectral features of warm absorbers (dust-free WAs, dusty WAs, peculiar ~1.1 keV absorption, emission and reflection components) and then discuss these in more detail based on analyses of individual objects observed with the X-ray satellite ROSAT. The importance of XMM in improving our knowledge of the warm material is discussed.

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Stefanie Komossa. 1998-11-03. The complex X-ray spectra of active galaxies with warm absorbers. https://arxiv.org/abs/astro-ph/9811049

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