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arXiv · 0803.0896

The broad-band XMM-Newton and INTEGRAL spectra of bright type 1 Seyfert galaxies

F. Panessa·L. Bassani·A. De Rosa·A. J. Bird·A. J. Dean·M. Fiocchi·A. Malizia·M. Molina·P. Ubertini·R. Walter
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Abstract

The 0.5-150 keV broad-band spectra of a sample of nine bright type 1 Seyfert galaxies are analyzed here. These sources have been discovered/detected by INTEGRAL and subsequently observed with XMM--Newton for the first time with high sensitivity below 10 keV. The sample, although small, is representative of the population of type 1 AGN which are now being observed above 20 keV. The intrinsic continuum has been modeled using three different parameterizations: a power-law model, an exponential cut-off power-law and an exponential cut-off power-law with a Compton reflection component. In each model the presence of intrinsic absorption, a soft component and emission line reprocessing features has also been tested. A simple power-law model is a statistically good description of most of the spectra presented here; an FeK line, fully and/or partial covering absorption and a soft spectral component are detected in the majority of the sample sources. The average photon index (< Gamma > = 1.7 $\pm$ 0.2) is consistent, within errors, with the canonical spectral slope often observed in AGN although the photon index distribution peaks in our case at flat Gamma (~ 1.5) values. For four sources, we find a significantly improved fit when the power-law is exponentially cut-off at an energy which is constrained to be below ~ 150 keV. The Compton reflection parameter could be estimated in only two objects of the sample and in both cases is found to be R > 1.

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F. Panessa, L. Bassani, A. De Rosa, A. J. Bird, A. J. Dean, M. Fiocchi, A. Malizia, M. Molina, P. Ubertini, R. Walter. 2008-03-06. The broad-band XMM-Newton and INTEGRAL spectra of bright type 1 Seyfert galaxies. https://doi.org/10.1051/0004-6361:20078657

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