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arXiv · astro-ph/0101079

BeppoSAX Observations of the Seyfert-2 Galaxies NGC 7172 and ESO 103-G35

Abstract

We investigate the X-ray spectra of the type-2 Seyfert galaxies NGC 7172 and ESO 103-G35, using BeppoSAX observations, separated by approximately one year. We find that the X-ray spectra of both NGC 7172 and ESO 103-G35 can be well fitted using a power-law model with an Fe K emission line at 6.4 keV. We did not find any statistically significant evidence for the existence of a reflection component in the X-ray spectra of these two galaxies. The continuum flux has decreased by a factor of approximately two during this period, in both objects. However, the spectral index as well as the absorption column have remained constant. We find weak evidence for the decrease of the normalization of the Fe K emission line in a similar manner to the continuum in NGC7172. We also report evidence for a broad Fe K confirming previous observations. In contrast, in the case of ESO 103-G35 the line flux does not change while its width remains unresolved.

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BibTeXRIS

A. Akylas, I. Georgantopoulos, A. Comastri. 2001-01-05. BeppoSAX Observations of the Seyfert-2 Galaxies NGC 7172 and ESO 103-G35. https://doi.org/10.1046/j.1365-8711.2001.04375.x

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