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arXiv · astro-ph/0010524

The unique rapid variabilities of the iron K$α$ line profiles in NGC 4151

Abstract

We present a detailed analysis of the iron K$α$ line variabilities in NGC 4151 by using long ASCA observation data obtained in May 1995. Despite the relatively small amplitude variations in the continuum flux, the iron K$α$ line flux and profile show dramatic variations. Particularly, the line profile changes from single peak to seeming double peaks and back in time scales of a few 10$^4$ sec. The seemingly double-peaked profiles can be well interpreted as line emission from a Keplerian ring around a massive black hole. An absorption line at around 5.9 keV is also marginnaly detected. We discussed current Fe K line models, but none of them can well explain the observed line and continuum variations.

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Jun-xian Wang, Ting-gui Wang, You-yuan Zhou. 2000-10-25. The unique rapid variabilities of the iron K$α$ line profiles in NGC 4151. https://doi.org/10.1086/319471

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