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arXiv · astro-ph/0302551

Multiwavelength studies of the Seyfert 1 galaxy NGC7469. II - X-ray and UV observations with XMM-Newton

Abstract

We present an XMM-Newton observation of NGC 7469, including studies of the X-ray and UV variability, 0.2-10 keV spectral continuum, Fe K-alpha emission line and the first-ever high-resolution X-ray spectrum of the soft X-ray warm absorber. We compare the properties of this X-ray warm absorber with the UV warm absorber as seen in a FUSE observation one year previously. The 0.2-10 keV spectral continuum is best fitted by a power-law plus two blackbody model. An Fe K-alpha emission line is visible which consists of a single narrow component and is well-modelled by a simple gaussian. Narrow absorption and emission lines in the soft X-ray RGS spectrum demonstrate the existence of a multi-phase warm absorber with a range in log xi of ~ 2 to ~ -2 where xi is in erg cm s^-1. The warm absorber is blueshifted by several hundred km s^-1. The highest-ionisation phase of the absorber is the best constrained and has an overall equivalent Hydrogen column of order 10^20 cm^-2; we find that its ionisation parameter is consistent with that of the warm emitter which generates the narrow emission lines. We identify this high ionisation absorber with the low-velocity phase of the UV absorber observed by FUSE.

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BibTeXRIS

A. J. Blustin, G. Branduardi-Raymont, E. Behar, J. S. Kaastra, G. A. Kriss, M. J. Page, S. M. Kahn, M. Sako, K. C. Steenbrugge. 2003-02-26. Multiwavelength studies of the Seyfert 1 galaxy NGC7469. II - X-ray and UV observations with XMM-Newton. https://doi.org/10.1051/0004-6361%3A20030236

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