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4U 1344-60: a bright intermediate Seyfert galaxy at z=0.012 with a relativistic Fe Kalpha emission line

E. Piconcelli·M. Sanchez-Portal·M. Guainazzi·A. Martocchia·C. Motch·A. C. Schroeder·S. Bianchi·E. Jimenez-Bailon·G. Matt
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Abstract

We present analysis of the optical and X-ray spectra of the low Galactic latitude bright (F(2-10) = 3.6 10^{-11} erg/cm2/s) source 4U 1344-60. On the basis of the optical data we propose to classify 4U 1344-60 as an intermediate type Seyfert galaxy and we measure a value of z=0.012+/-0.001 for its redshift. From the XMM-Newton observation we find that the overall X-ray spectral shape of 4U 1344-60 is complex and can be described by a power-law continuum (Gamma ~ 1.55) obscured by two neutral absorption components (Nh(f) ~ 10^{22} cm^{-2} and Nh(p) ~ 4 10^{22} cm^{-2}), the latter covering only the ~50% of the primary X-ray source. The X-ray data therefore lend support to our classification of 4U 1344-60. It exhibits a broad and skewed Fe Kalpha line at 6.4 keV, which suggests the existence of an accretion disk that is able to reprocess the primary continuum down to a few gravitational radii. Such a line represents one of the clearest examples of a relativistic line observed by XMM-Newton so far. Our analysis has also revealed the marginal presence of two narrow line-like emission features at ~4.9 and ~5.2 keV.

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E. Piconcelli, M. Sanchez-Portal, M. Guainazzi, A. Martocchia, C. Motch, A. C. Schroeder, S. Bianchi, E. Jimenez-Bailon, G. Matt. 2006-03-27. 4U 1344-60: a bright intermediate Seyfert galaxy at z=0.012 with a relativistic Fe Kalpha emission line. https://doi.org/10.1051/0004-6361%3A20064956

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