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BeppoSAX view of radio-loud Active Galactic Nuclei

Paola Grandi·Giuseppe Malaguti·Mariateresa Fiocchi·--
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Abstract

A systematic analysis of a large sample of radio-loud Active Galactic Nuclei available in the BeppoSAX public archive has been performed. The sample includes 3 Narrow Line Radio Galaxies (NLRG), 10 Broad Line Radio Galaxies (BLRG), 6 Steep Spectrum Radio Quasars (SSRQ), and 16 Flat Spectrum Radio Quasars (FSRQ). According to the unified models, these classes correspond to objects with increasing viewing angles. As expected, the presence of a non-thermal beamed component emerges clearly in FSRQ. This class shows in fact a featureless continuum (with the exception of 3C273), and a significantly flatter average spectral slope. On the contrary, traces of a non-thermal Doppler enhanced radiation are elusive in the other classes. We find that the iron line equivalent widths (EW) are generally weaker in radio- loud AGN than in Seyfert 1 galaxies, and confirm the presence of an X-ray Baldwin effect, i.e. a decrease of EW with the 2--10 keV luminosity (L) from Seyferts to BLRG and quasars. Since the EW--L anti-correlation is present also in radio-quiet AGN alone, this effect cannot be ascribed entirely to a strongly beamed jet component. Possible alternative interpretations are explored.

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Paola Grandi, Giuseppe Malaguti, Mariateresa Fiocchi, --. 2005-11-29. BeppoSAX view of radio-loud Active Galactic Nuclei. https://doi.org/10.1086/500100

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