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arXiv · 0902.0930

Suzaku observation of the Phoenix Galaxy

G. Matt·S. Bianchi·H. Awaki·A. Comastri·M. Guainazzi·K. Iwasawa·E. Jimenez-Bailon·F. Nicastro
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Abstract

In recent years, several Seyfert 2 galaxies have been discovered that change state when observed in X-rays a few years apart, switching from Compton-thin to reflection-dominated or viceversa. We observed a member of this class of "Changing-look" sources, the Phoenix Galaxy, with Suzaku, with the aim of better understanding the nature of the variations. The Suzaku spectrum was analyzed, and the results compared with previous ASCA and XMM-Newton observations. The source was caught in a Compton-thin state, as in XMM-Newton, but differently from ASCA. Comparing the Suzaku and XMM-Newton observations, a variation in the column density of the absorber on a time scale of years is discovered. A similar change, but on much shorter time scales (i.e. ks) may also explain the count-rate variations during the Suzaku observations. A soft excess is also present, likely due to continuum and line emission from photoionized circumnuclear matter.

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G. Matt, S. Bianchi, H. Awaki, A. Comastri, M. Guainazzi, K. Iwasawa, E. Jimenez-Bailon, F. Nicastro. 2009-02-05. Suzaku observation of the Phoenix Galaxy. https://doi.org/10.1051/0004-6361%2F200811049

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