Mao, J;
Kaastra, J;
Mehdipour, M;
Gu, L;
Costantini, E;
Kriss, G;
Bianchi, S;
... Ebrero, J; + view all
(2018)
Anatomy of the AGN in NGC 5548 IX. Photoionized emission features in the soft X-ray spectra.
Astronomy and Astrophysics
10.1051/0004-6361/201732162.
(In press).
Preview |
Text
Branduardi Raymont_aa32162-17.pdf - Published Version Download (1MB) | Preview |
Abstract
The X-ray narrow emission line region (NELR) of the archetypal Seyfert 1 galaxy NGC 5548 has been interpreted as a single-phase photoionized plasma that is absorbed by some of the warm absorber components. This scenario requires these overlaying warm absorber components to be at a greater distance (from the central engine) than the X-ray NELR, which is not fully consistent with the distance estimates found in the literature. Therefore, we reanalyze the high-resolution spectra obtained in 2013–2014 with the Reflection Grating Spectrometer (RGS) on board XMM-Newton to provide an alternative interpretation of the X-ray narrow emission features. We find that the X-ray narrow emission features in NGC 5548 can be described by a two-phase photoionized plasma with different ionization parameters (log ξ = 1.3 and 0.1) and kinematics (vout = −50 and −400 km s−1 ), but no further absorption by the warm absorber components. The X-ray and optical NELR might be the same multiphase photoionized plasma. The X-ray and the optical NELRs have comparable distances and asymmetric line profiles, and the underlying photoionized plasma is turbulent and compact in size. The X-ray NELR is not the counterpart of the UV/X-ray absorber outside the line of sight because their distances and kinematics are not consistent. In addition, X-ray broad emission features that we find in the spectrum can be accounted for by a third photoionized emission component. The RGS spectrum obtained in 2016 is analyzed as well, where the luminosity of most prominent emission lines (the O vii forbidden line and O viii Lyα line) are the same (at a 1 σ confidence level) as in 2013–2014.
| Type: | Article |
|---|---|
| Title: | Anatomy of the AGN in NGC 5548 IX. Photoionized emission features in the soft X-ray spectra |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1051/0004-6361/201732162 |
| Publisher version: | http://doi.org/10.1051/0004-6361/201732162 |
| Language: | English |
| Additional information: | © ESO 2018. This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | X-rays: galaxies – galaxies: active – galaxies: Seyfert – galaxies: individual: NGC 5548 – techniques: spectroscopic |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Space and Climate Physics |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/10045498 |
Archive Staff Only
 |
View Item |
