Suzaku observation of the Phoenix Galaxy

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.

Accepted for publication in Astronomy & Astrophysics

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Cited by in corpus (11)

• Three years Swift-BAT Survey of AGN: reconciling theory and observations?
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• Suzaku Observations of Moderately Obscured (Compton-thin) Active Galactic Nuclei Selected by Swift/BAT Hard X-ray Survey
• Chandra monitoring of UGC 4203: the structure of the X-ray absorber
• X-ray spectral variability of Seyfert 2 galaxies
• The INTEGRAL/IBIS AGN catalogue: an update
• Modelling the X-ray polarimetric signatures of complex geometry: the case study of the "changing look" AGN NGC 1365
• Multi-Zone warm and cold clumpy absorbers in 3 Seyfert galaxies
• Compton Shoulder Diagnostics in Active Galactic Nuclei for Probing the Metalicity of the Obscuring Compton-Thick Tori
• The Phoenix galaxy as seen by NuSTAR
• Serendipitous Discovery of Warm Absorbers in the Seyfert 2 Galaxy IRAS 18325-5926