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arXiv · 0907.0405

First high-resolution detection of a warm absorber in the Broad Line Radio Galaxy 3C 382

E. Torresi·P. Grandi·A. L. Longinotti·M. Guainazzi·G. G. C. Palumbo·F. Tombesi·A. Nucita
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Abstract

Recent high-resolution measurements suggest that the soft X-ray spectrum of obscured Radio Galaxies (RG) exhibits signatures of photoionised gas (e.g. 3C 445 and 3C 33) similar to those observed in radio-quiet obscured Active Galactic Nuclei (AGN). While signatures of warm absorbing gas covering a wide range of temperature and ionisation states have been detected in about one half of the population of nearby Seyfert 1 galaxies, no traces of warm absorber gas have been reported to date in the high-resolution spectra of Broad Line Radio Galaxies (BLRG). We present here the first detection of a soft X-ray warm absorber in the powerful FRII BLRG 3C 382 using the Reflection Grating Spectrometer (RGS) on-board XMM-Newton. The absorption gas appears to be highly ionised, with column density of the order of 10^{22} cm^{-2}, ionisation parameter log\xi>2 erg cm s^{-1} and outflow velocities of the order of 10^{3} km s^{-1}. The absorption lines may come from regions located outside the torus, however at distances less than 60 pc. This result may indicate that a plasma ejected at velocities near the speed of light and a photoionised gas with slower, outflow velocities can coexist in the same source beyond the Broad Line Regions.

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E. Torresi, P. Grandi, A. L. Longinotti, M. Guainazzi, G. G. C. Palumbo, F. Tombesi, A. Nucita. 2009-07-02. First high-resolution detection of a warm absorber in the Broad Line Radio Galaxy 3C 382. https://doi.org/10.1111/j.1745-3933.2009.00773.x

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