Active galaxy 4U 1344-60: did the relativistic iron line disappear?
Abstract
X-ray bright active galactic nuclei represent a unique astrophysical laboratory for studying accretion physics around super-massive black holes. 4U 1344-60 is a bright Seyfert galaxy that revealed relativistic reflection features in the archival XMM-Newton observation. I will present the spectroscopic results of new data obtained with the Suzaku satellite and compare them with the previous observation. The X-ray continuum of 4U 1344-60 can be well described by a power-law component with the photon index 1.7 modified by a fully and a partially covering local absorbers. We measured a substantial decrease of the fraction of the partially absorbed radiation from around 45% to less than 10% while the power-law slope remains constant within uncertainties. The iron line in the Suzaku spectrum is relatively narrow, without any suggestion for relativistic broadening. Regarding this we interpret the iron line complex in the archival XMM-Newton spectrum as a narrow line plus an enhanced emission from the innermost accretion flow. The detected red-shifted iron line emission is probably a temporarily enhanced emission from the innermost accretion flow during the XMM-Newton observation.
- Publication:
-
Half a Century of X-ray Astronomy
- Pub Date:
- September 2012
- Bibcode:
- 2012hcxa.confE..49S