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arXiv · 0901.3351

3C 33: another case of photoionized soft X-ray emission in radio galaxies

E. Torresi·P. Grandi·M. Guainazzi·G. G. C. Palumbo·G. Ponti·S. Bianchi
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Abstract

All the observations available in the Chandra and XMM-Newton archives have been used to investigate the X-ray spectral properties of 3C 33. In this paper is presented a complete X-ray analysis of the nuclear emission of this narrow line radio galaxy. The broad band spectrum of 3C 33 is complex. The hard part resembles that of Seyfert 2 galaxies, with a heavily obscured nuclear continuum (N_H~10^23 cm^-2) and a prominent Fe Kalpha line. This represents the nuclear radiation directly observed in transmission through a cold circumnuclear gas. On the other hand an unabsorbed continuum plus emission lines seem to fit well the soft part of the spectrum (0.5-2 keV) suggesting that the jet does not significantly contribute to the X-ray emission. We discuss the possible collisional or photoionized origin of the gas that emits the soft X-ray lines. Our results, strengthened by optical spectroscopy favor the photoionization scenario.

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E. Torresi, P. Grandi, M. Guainazzi, G. G. C. Palumbo, G. Ponti, S. Bianchi. 2009-01-21. 3C 33: another case of photoionized soft X-ray emission in radio galaxies. https://doi.org/10.1051/0004-6361%2F200810944

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