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On the nature of the X-ray absorption in the Seyfert 2 galaxy NGC 4507

A. Comastri·C. Vignali·M. Cappi·G. Matt·R. Audano·H. Awaki·S. Ueno
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Abstract

We present results of the ASCA observation of the Seyfert 2 galaxy NGC 4507. The 0.5-10 keV spectrum is rather complex and consists of several components: (1) a hard X-ray power law heavily absorbed by a column density of about 3 10^23 cm^-2, (2) a narrow Fe Kalpha line at 6.4 keV, (3) soft continuum emission well above the extrapolation of the absorbed hard power law, (4) a narrow emission line at about 0.9 keV. The line energy, consistent with highly ionized Neon (NeIX), may indicate that the soft X-ray emission derives from a combination of resonant scattering and fluorescence in a photoionized gas. Some contribution to the soft X-ray spectrum from thermal emission, as a blend of Fe L lines, by a starburst component in the host galaxy cannot be ruled out with the present data.

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A. Comastri, C. Vignali, M. Cappi, G. Matt, R. Audano, H. Awaki, S. Ueno. 1997-10-28. On the nature of the X-ray absorption in the Seyfert 2 galaxy NGC 4507. https://doi.org/10.1046/j.1365-8711.1998.01302.x

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