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

TL;DR

This paper reports the first detection of a warm absorber in a Broad Line Radio Galaxy, revealing highly ionised gas with outflow velocities, expanding understanding of AGN environments.

Contribution

It presents the first high-resolution detection of a warm absorber in the BLRG 3C 382, showing coexistence of different plasma components beyond the Broad Line Regions.

Findings

Detection of highly ionised warm absorber in 3C 382

Absorber has column density ~10^{22} cm^{-2}

Outflow velocities around 10^{3} km s^{-1}

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.