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An Infrared View of Local Universe AGN

Almudena Alonso-Herrero
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Abstract

We summarize recent results on the infrared (IR) nuclear properties of Seyfert galaxies. 100% of all Seyfert 1-1.9$ and ~50% of all Seyfert 2s in the CfA and RSA samples observed with HST/NICMOS show nuclear point sources at 1.6micron. We find that the unresolved emission is variable in 9 out of the 14 Seyferts with duplicate observations, indicating a non-stellar origin. We have also put together non-stellar 0.4-16micron spectral energy distributions (SEDs) for the entire CfA sample of Seyfert galaxies. The shape of the SEDs for a complete sample of AGN can be used to constrain torus models.We report a good correlation between the IR and hard X-ray luminosities of local universe AGN suggesting that their mid-IR emission is approximately an isotropic property, and thus can be used as an indicator of the AGN luminosity. Finally we show that the hard X-ray and mid-IR luminosities appear to be related to the black hole mass in AGN.

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Almudena Alonso-Herrero. 2002-11-21. An Infrared View of Local Universe AGN. https://arxiv.org/abs/astro-ph/0211484

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