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Chandra LETGS and XMM-Newton observations of NGC 4593

K. C. Steenbrugge·J. S. Kaastra·A. J. Blustin·G. Branduardi-Raymont·M. Sako·E. Behar·S. M. Kahn·F. B. S. Paerels·R. Walter
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Abstract

In this paper, we analyze spectra of the Seyfert 1 galaxy NGC 4593 obtained with the Chandra Low Energy Transmission Grating Spectrometer (LETGS), the Reflection Grating Spectrometer (RGS) and the European Photon Imaging Camera's (EPIC) onboard of XMM-Newton. The two observations were separated by ~7 months. In the LETGS spectrum we detect a highly ionized warm absorber corresponding to an ionization state of 400x10^{-9} W m, visible as a depression at 10-18 Å. This depression is formed by multiple weak Fe and Ne lines. A much smaller column density was found for the lowly ionized warm absorber, corresponding to xi = 3x10^{-9} W m. However, an intermediate ionization warm absorber is not detected. For the RGS data the ionization state is hard to constrain. The EPIC results show a narrow Fe Kalpha line.

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K. C. Steenbrugge, J. S. Kaastra, A. J. Blustin, G. Branduardi-Raymont, M. Sako, E. Behar, S. M. Kahn, F. B. S. Paerels, R. Walter. 2003-06-17. Chandra LETGS and XMM-Newton observations of NGC 4593. https://doi.org/10.1051/0004-6361%3A20031021

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