Suzaku Studies of Wide-Band Spectral Variability of the Bright Type I Seyfert Galaxy Markarian 509
Abstract
The Type I Seyfert galaxy Markarian 509 was observed with Suzaku in 2010 November, for a gross time span of 2.2 days. The timing and spectral properties of the 0.5-45 keV X-rays, detected with the XIS and HXD, consistently revealed the presence of a soft spectral component that remained constant while the total X-ray intensity varied by ±10%. This stable soft component, found in the 0.5-3.0 keV range, was interpreted as being a result of thermal Comptonization in a corona with a temperature of ∼0.5 keV and an optical depth of ∼18. The time-avearged 0.5-45 keV Suzaku spectrum was reproduced successfully, as a combination of this thermal Comptonization component, a harder power-law of photon index ∼1.8, moderate reflection, and an iron K-emission line. By analyzing four archival Suzaku datasets of the same object obtained in 2006, the thermal Comptonization component, which was stable during 2.2-day pointing in 2010, was found to vary on time scales of a few weeks, independently of the power-law component. Implications of these results are discussed in terms of a ``multi-zone Comptonization'' view, obtained with Suzaku from the black-hole binary Cygnus X-1.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- November 2011
- DOI:
- 10.1093/pasj/63.sp3.S925
- arXiv:
- arXiv:1109.0457
- Bibcode:
- 2011PASJ...63S.925N
- Keywords:
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- galaxies: active;
- galaxies: individual (Mrk 509);
- galaxies: Seyfert;
- X-rays: galaxies;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 12 pages, 9 figures