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Transmission- to reflection-dominated transition in Seyfert 2 galaxies: the XMM-Newton view

M. Guainazzi·P. Rodriguez-Pascual·A. C. Fabian·K. Iwasawa·G. Matt·F. Fiore
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Abstract

In this paper we present the current status of a XMM-Newton program to observe an optically-defined, complete and unbiased sample of Compton-thick Seyfert 2 galaxies. The main goal of this project is the measurement of the occurrence rate of transition between transmission- (i.e.: Compton-thin), and reflection-dominated spectral states. These transitions potentially provide information on the distribution of the obscuring matter surrounding the nucleus, and on the duty-cycle of the AGN activity. With about 2/3 of the whole sample being observed, we detected 1 further transition out of 8 observed objects, confirming previous suggestions that these transitions occur on time-scales ~50-100 years.

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M. Guainazzi, P. Rodriguez-Pascual, A. C. Fabian, K. Iwasawa, G. Matt, F. Fiore. 2004-04-01. Transmission- to reflection-dominated transition in Seyfert 2 galaxies: the XMM-Newton view. https://doi.org/10.1142/9789812702432_0058

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