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Do Normal Galaxies Host a Black Hole? The High Energy Perspective

Y. Terashima
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Abstract

We review ASCA results on a search for low luminosity active nuclei at the center of nearby normal galaxies. More than a dozen low-luminosity AGN have been discovered with 2-10 keV luminosity in the range 10^{40-41} ergs/s. Their X-ray properties are in some respects similar to those of luminous Seyfert galaxies, but differ in other respects. We also present estimated black hole masses in low luminosity AGNs and a drastic activity decline in the nucleus of the radio galaxy Fornax A. These results altogether suggest that relics of the past luminous AGNs lurk in nearby normal galaxies.

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Y. Terashima. 1999-05-17. Do Normal Galaxies Host a Black Hole? The High Energy Perspective. https://arxiv.org/abs/astro-ph/9905218

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