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Seyfert 1 mutation of the classical Seyfert 2 nucleus NGC 7582

Itziar Aretxaga·B. Joguet·D. Kunth·J. Melnick·R. J. Terlevich
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Abstract

We report the transition towards a type 1 Seyfert experienced by the classical type 2 Seyfert nucleus in NGC 7582. The transition, found at most 20 days from its maximum peak, presents a unique opportunity to study these rare events in detail. At maximum the Ha line width is of about 12000 km/s. We examine three scenarios that could potentially explain the transition: capture of a star by a supermassive black hole, a reddening change in the surrounding torus, and the radiative onset of a type IIn supernova exploding in a compact nuclear/circumnuclear starburst.

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Itziar Aretxaga, B. Joguet, D. Kunth, J. Melnick, R. J. Terlevich. 1999-05-12. Seyfert 1 mutation of the classical Seyfert 2 nucleus NGC 7582. https://doi.org/10.1086/312114

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