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Implications of IR continua for x-ray emission/reflection in AGN

Gary J. Ferland·Peter G. Martin·Peter A. M. van Hoof·Joseph C. Weingartner
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Abstract

Observations of infrared emission from AGN show that grains exist over a broad range of distances from the central object, extending to the point where they are destroyed by sublimation. These ~1000 K grains produce much of the 1 micron continuum. In this region closest to the central object there must be a gaseous component associated with the hot grains. This paper employs a state of the art grain model and shows that the gas must be very hot, with temperatures in the neighborhood of 10^6 K. The dusty component has a covering factor of roughly 50% and so this region also reprocesses much of the total x-ray emission. Our explicit models of the IR through x-ray spectral energy distributions allow the x-ray component to be predicted from IR observations. We are creating a grid of such predictions and will make them available as an XSPEC add-in, allowing this spectral component to be included in quantitative modeling of AGN spectra.

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Gary J. Ferland, Peter G. Martin, Peter A. M. van Hoof, Joseph C. Weingartner. 2003-11-22. Implications of IR continua for x-ray emission/reflection in AGN. https://arxiv.org/abs/astro-ph/0311520

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