Discovery of Relativistic Outflow in the Seyfert Galaxy Ark 564

Abstract

We present \chandra high energy transmission grating spectra of the narrow-line Seyfert-1 galaxy Ark 564. The spectrum shows numerous absorption lines which are well modeled with low velocity outflow components usually observed in Seyfert galaxies \citep{Gupta2013}. There are, however, some residual absorption lines which are not accounted for by low-velocity outflows. Here we present identifications of the strongest lines as $K\alpha$ transitions of \oviin (two lines) and \ovin at outflow velocities of $\sim 0.1c$. These lines are detected at $6.9\sigma$, $6.2\sigma$, and $4.7\sigma$ respectively and cannot be due to chance statistical fluctuations. Photoionization models with ultra-high velocity components improves the spectral fit significantly, providing further support for the presence of relativistic outflow in this source. Without knowing the location of the absorber, its mass and energy outflow rates cannot be well constrained; we find $\dot{E}(outflow)/L_{bol}$ lower limit of $\ge 0.006$% assuming a bi-conical wind geometry. This is the first time that absorption lines with ultra-high velocities are unambiguously detected in the soft X-ray band. The presence of outflows with relativistic velocities in AGNs with Seyfert-type luminosities is hard to understand and provides valuable constraints to models of AGN outflows. Radiation pressure is unlikely to be the driving mechanism for such outflows and magneto-hydrodynamic may be involved.

Accepted for publication in ApJ

References in corpus (6)

• Unification of X-ray winds in Seyfert galaxies: from ultra-fast outflows to warm absorbers
• On the Fraction of Quasars with Outflows
• Multi-dimensional modelling of X-ray spectra for AGN accretion-disk outflows
• An axisymmetric hydrodynamical model for the torus wind in AGN. II: X-ray excited funnel flow
• XMM-Newton observation of the NLS1 Galaxy Ark 564: I. Spectral analysis of the time-average spectrum
• A Two-Phase Low-velocity Outflow in the Seyfert 1 Galaxy Ark~564

Cited by in corpus (33)

• Ionized outflows from active galactic nuclei as the essential elements of feedback
• Dynamics of Dusty Radiation Pressure Driven Shells and Clouds: Fast Outflows from Galaxies, Star Clusters, Massive Stars, and AGN
• Ultra-fast outflows in radio-loud active galactic nuclei
• Radio-emitting narrow-line Seyfert 1 galaxies in the JVLA perspective
• Ultrafast outflows disappear in high radiation fields
• X-ray high-resolution spectroscopy reveals feedback in a Seyfert galaxy from an ultra fast wind with complex ionization and velocity structure
• Multiphase quasar-driven outflows in PG 1114+445. I. Entrained ultra-fast outflows
• Resolving the soft X-ray ultra fast outflow in PDS 456
• Discovery of Broad Soft X-ray Absorption Lines from the Quasar Wind in PDS 456
• The variable, fast soft X-ray wind in PG 1211+143
• Detection of high velocity outflows in Seyfert 1 galaxy Mrk 590
• The XMM deep survey in the CDF-S. IX. An X-ray outflow in a luminous obscured quasar at z~1.6
• Tell-Tale Spectral Signatures of MHD-driven Ultra-Fast Outflows in AGNs
• Narrow absorption lines with two observations of Sloan Digital Sky Survey
• Dynamical thermal instability in highly supersonic outflows
• Detection of a Multi-Phase Ultra-Fast Wind in the Narrow-Line Seyfert 1 Galaxy Mrk 1044
• Emergences of C IV narrow absorption troughs in the quasar SDSS J095254.10+021932.8
• X-ray Reverberation Mapping of Ark 564 using Gaussian Process Regression
• Scientific Objectives of the Hot Universe Baryon Surveyor (HUBS) Mission
• Chemical abundances along the quasar main sequence
• Accretion disk winds in active galactic nuclei: X-ray observations, models, and feedback
• Revealing a hard X-ray spectral component that reverberates within one light hour of the central supermassive black hole in Ark 564
• Supermassive Black Hole Winds in X-rays: SUBWAYS. II. HST UV spectroscopy of winds at intermediate redshifts
• Star formation efficiency and AGN feedback in narrow-line Seyfert 1 galaxies with fast X-ray nuclear winds
• Narrow C IV absorption doublets on quasar spectra of the Baryon Oscillation Spectroscopic Survey
• Large-scale Dynamics of Winds Driven by Line Force from a Thin Accretion Disk
• The Close AGN Reference Survey (CARS). A parsec scale multi-phase outflow in the super-Eddington NLS1 Mrk 1044
• The XMM-Newton and NuSTAR view of IRASF11119+3257. I Detection of multiple UFO components and a very cold corona
• Constraining X-ray Coronal Size with Transverse Motion of AGN Ultra-Fast Outflows
• Hubble Space Telescope Observations of BALQSO Ton 34 Reveal a Connection between the Broad Line Region and the BAL Outflow
• Fast Outflowing Warm Absorbers in Narrow-Line Seyfert 1 Galaxy PG 1001+054 Revealed by HST/COS Spectra
• UV counterpart of an X-ray ultra-fast outflow in IRAS 17020+4544
• Unravelling the origin of extended radio emission in narrow-line Seyfert 1 galaxies with the JVLA