Suzaku observation of the Phoenix galaxy
Abstract
Context: 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.
Aims: 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.
Methods: The {Suzaku} spectrum was analyzed, and the results compared with previous ASCA and XMM-Newton observations.
Results: 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.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 2009
- DOI:
- 10.1051/0004-6361/200811049
- arXiv:
- arXiv:0902.0930
- Bibcode:
- 2009A&A...496..653M
- Keywords:
-
- galaxies: active;
- galaxies: Seyfert;
- galaxies:;
- individual: Phoenix;
- X-rays: galaxies;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Cosmology and Extragalactic Astrophysics
- E-Print:
- Accepted for publication in Astronomy &