1 research outputs found
Suzaku observation of the Phoenix Galaxy
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.Comment: Accepted for publication in Astronomy & Astrophysic