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X-RAY OUTBURST OF THE PECULIAR SEYFERT GALAXY IC 3599

D. Grupe·K. Beuermann·K. Mannheim·N. Bade·H. -C. Thomas·D. de Martino·A. Schwope
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Abstract

We report optical, soft X-ray, and UV observations of the peculiar Seyfert galaxy IC 3599 using data obtained with ROSAT and IUE. Most remarkably, we discovered a rapid decrease of the X-ray flux by a factor of about 100 within one year and a more gradual decrease thereafter. The X-ray spectrum of IC 3599 was soft at flux maximum and became even softer as the flux decreased. Simultaneously with the late decrease of the X-ray flux, we observed a decrease in the strength of highly ionized optical iron lines. We discuss several explanations for this behaviour including an accretion disk instability and tidal disruption of a star orbiting a central massive black hole.

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D. Grupe, K. Beuermann, K. Mannheim, N. Bade, H. -C. Thomas, D. de Martino, A. Schwope. 1995-05-18. X-RAY OUTBURST OF THE PECULIAR SEYFERT GALAXY IC 3599. https://arxiv.org/abs/astro-ph/9505085

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