Anatomy of the AGN in NGC 5548 IX. Photoionized emission features in the soft X-ray spectra

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 those overlaying warm absorber components to have larger distance (to 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) aboard \textit{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 ($\log \xi =1.3$ and $0.1$) and kinematics ($v_{\mathrm{out}}=-50$ and $-400\mathrm{km}{\mathrm{s}}^{-1}$), and no further absorption by the warm absorber components. The X-ray and optical NELR might be the same multi-phase photoionized plasma. Both X-ray and optical NELR have comparable distances, 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 \ion{O}{vii} forbidden line and \ion{O}{viii} Ly$\alpha$ line) are the same (at a 1 $\sigma$ confidence level) as in 2013--2014.

arXiv commentaccepted for publication in A&A

References in corpus (59)

• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
• Revisiting the Unified Model of Active Galactic Nuclei
• Optimal binning of X-ray spectra and response matrix design
• Reverberation Measurements of the Inner Radius of the Dust Torus in Nearby Seyfert 1 Galaxies
• The nature and origin of Seyfert warm absorbers
• X-ray photoionized plasma diagnostics with Helium-like ions. Application to Warm Absorber-Emitter in Active Galactic Nuclei
• XMM-Newton Reflection Grating Spectrometer Observations of Discrete Soft-X-ray Emission Features from NGC 1068
• A fast and long-lived outflow from the supermassive black hole in NGC 5548
• On the use of C-stat in testing models for X-ray spectra
• The soft X-ray/NLR connection: a single photoionized medium?
• Steps Toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XVI. A Thirteen-Year Study of Spectral Variability in NGC 5548
• Observable Properties of X-ray Heated Winds in AGN: Warm Reflectors and Warm Absorbers
• Anatomy of the AGN in NGC 5548: I. A global model for the broadband spectral energy distribution
• On the origin of soft X-rays in obscured AGN: answers from high-resolution spectroscopy with XMM-Newton
• Simultaneous X-ray and UV spectroscopy of the Seyfert 1 galaxy NGC 5548.II. Physical conditions in the X-ray absorber
• X-ray spectroscopy of NGC 5548
• Simultaneous EUVE/ASCA/RXTE Observations of NGC 5548
• Size and properties of the narrow-line region in Seyfert-1 galaxies from spatially-resolved optical spectroscopy
• Size and properties of the narrow-line region in Seyfert-2 galaxies from spatially-resolved optical spectroscopy
• The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability
• Systematic comparison of photoionised plasma codes with application to spectroscopic studies of AGN in X-rays
• Ionized Absorbers in AGN: the Role of Collisional Ionization and Time-Evolving Photoionization
• X-Ray/Ultraviolet Observing Campaign of the Markarian 279 Active Galactic Nucleus Outflow: a close look at the absorbing/emitting gas with Chandra-LETGS
• Chasing obscuration in type-I AGN: discovery of an eclipsing clumpy wind at the outer broad-line region of NGC 3783
• Multiwavelength campaign on Mrk 509 VIII. Location of the X-ray absorber
• Anatomy of the AGN in NGC 5548: II. The Spatial, Temporal and Physical Nature of the Outflow from HST/COS Observations
• Winds from accretion disks driven by the radiation and magnetocentrifugal force
• A novel scenario for the possible X-ray line feature at ~3.5 keV: Charge exchange with bare sulfur ions
• Possible Charge-Exchange X-Ray Emission in the Cygnus Loop Detected with Suzaku
• Radiation Pressure Confinement - I. Ionized Gas in the ISM of AGN Hosts
• Plasma code for astrophysical charge exchange emission at X-ray wavelengths
• Timing the warm absorber in NGC 4051
• X-ray spectroscopy on Abell 478 with XMM-Newton
• Warm Absorbers in X-rays (WAX), a comprehensive high resolution grating spectral study of a sample of Seyfert Galaxies: II. Warm Absorber dynamics and feedback to galaxies
• Anatomy of the AGN in NGC 5548 VIII. XMM-Newton's EPIC detailed view of an unexpected variable multilayer absorber
• A Census of X-ray gas in NGC 1068: Results from 450ks of Chandra HETG Observation
• The Seyfert 1 Galaxy Mrk 335 at a very low flux state: mapping the soft X-ray photoionised gas
• Evidence for a Physically Compact Narrow-Line Region in the Seyfert 1 Galaxy NGC 5548
• Density diagnostics of ionized outflows in active galactic nuclei: X-ray and UV absorption lines from metastable levels in Be-like to C-like ions
• Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL
• Measuring turbulence in the ISM by comparing N(HI;Lya) and N(HI;21cm)
• Anatomy of the AGN in NGC 5548: VII. Swift study of obscuration and broadband continuum variability
• Anatomy of the AGN in NGC 5548. VI. Long-term variability of the warm absorber
• High resolution X-ray spectroscopy and imaging of Mrk573
• AGN/starburst connection in action: the half million second RGS spectrum of NGC1365
• Multiwavelength campaign on Mrk 509. II. Analysis of high-quality Reflection Grating Spectrometer spectra
• A Photoionization Model For The Soft X-Ray Spectrum Of NGC 4151
• A characterization of the NGC 4051 soft X-ray spectrum as observed by XMM-Newton
• Anatomy of the AGN in NGC 5548: V. A clear view of the X-ray narrow emission lines
• The X-ray spectral signatures from the complex circumnuclear regions in the Compton thick AGN NGC 424
• Strong variability of the coronal line region in NGC 5548
• X-ray narrow line region variability as a geometry probe: The case of NGC 5548
• Multiwavelength campaign on Mrk 509 XV. A global modeling of the broad emission lines in the Optical, UV and X-ray bands
• The warm absorber in NGC 5548: The lean years
• On the Effects of Dissipative Turbulence on the Narrow Emission-Line Ratios in Seyfert Galaxies
• X-Ray Emission from Jupiter, Saturn, and Earth: A Short Review
• Science with hot astrophysical plasmas
• Charge exchange in the ultraviolet: implication for interacting clouds in the core of NGC 1275

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