Multiphase quasar-driven outflows in PG 1114+445

Substantial evidence in the last few decades suggests that outflows from supermassive black holes (SMBH) may play a significant role in the evolution of galaxies. These outflows, powered by active galactic nuclei (AGN), are thought to be the fundamental mechanism by which the SMBH transfers a significant fraction of its accretion energy to the surrounding environment. Large-scale outflows known as warm absorbers (WA) and fast disk winds known as ultra-fast outflows (UFO) are commonly found in the spectra of many Seyfert galaxies and quasars, and a correlation has been suggested between them. Recent detections of low ionization and low column density outflows, but with a high velocity comparable to UFOs, challenge such initial possible correlations. Observations of UFOs in AGN indicate that their energetics may be enough to have an impact on the interstellar medium (ISM). However, observational evidence of the interaction between the inner high-ionization outflow and the ISM is still missing. We present here the spectral analysis of 12 XMM-Newton/EPIC archival observations of the quasar PG 1114+445, aimed at studying the complex outflowing nature of its absorbers. Our analysis revealed the presence of three absorbing structures. We find a WA with velocity v ∼ 530 km s−1, ionization log ξ/erg cm s−1 ∼ 0.35, and column density log NH/cm−2 ∼ 22, and a UFO with vout ∼ 0.145c, log ξ/erg cm s−1 ∼ 4, and log NH/cm−2 ∼ 23. We also find an additional absorber in the soft X-rays (E < 2 keV) with velocity comparable to that of the UFO (vout ∼ 0.120c), but ionization (log ξ/erg cm s−1 ∼ 0.5) and column density (log NH/cm−2 ∼ 21.5) comparable with those of the WA. The ionization, velocity, and variability of the three absorbers indicate an origin in a multiphase and multiscale outflow, consistent with entrainment of the clumpy ISM by an inner UFO moving at ∼15% the speed of light, producing an entrained ultra-fast outflow (E-UFO).

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Compton-Thick AGN in the NuSTAR ERA VII. A joint NuSTAR, Chandra, and XMM-Newton Analysis of Two Nearby, Heavily Obscured Sources

The Astrophysical Journal ◽

10.3847/1538-4357/ac1fee ◽

2021 ◽

Vol 922 (2) ◽

pp. 159

Author(s):

A. Traina ◽

S. Marchesi ◽

C. Vignali ◽

N. Torres-Albà ◽

M. Ajello ◽

...

Keyword(s):

Spectral Analysis ◽

Energy Range ◽

Active Galactic Nuclei ◽

Column Density ◽

Galactic Nuclei ◽

Seyfert Galaxies ◽

Line Of Sight ◽

Broad Energy Range ◽

Larger Sample ◽

Broad Energy

Abstract We present the joint Chandra, XMM-Newton, and NuSTAR analysis of two nearby Seyfert galaxies, NGC 3081 and ESO 565-G019. These are the only two having Chandra data in a larger sample of 10 low-redshift (z ≤ 0.05), candidates Compton-thick (CT) Active Galactic Nuclei selected in the 15–150 keV band with Swift-BAT that were still lacking NuSTAR data. Our spectral analysis, performed using physically motivated models, provides an estimate of both the line-of-sight (l.o.s.) and average (N H,S ) column densities of the two torii. NGC 3081 has a Compton-thin l.o.s. column density N H,z = [0.58–0.62] × 1024 cm−2, but the N H,S , beyond the CT threshold (N H,S = [1.41–1.78] × 1024 cm−2), suggests a “patchy” scenario for the distribution of the circumnuclear matter. ESO 565-G019 has both CT l.o.s. and N H,S column densities (N H,z > 2.31 × 1024 cm−2 and N H,S > 2.57 × 1024 cm−2, respectively). The use of physically motivated models, coupled with the broad energy range covered by the data (0.6–70 keV and 0.6–40 keV, for NGC 3081 and ESO 565-G019, respectively) allows us to constrain the covering factor of the obscuring material, which is C TOR = [0.63–0.82] for NGC 3081, and C TOR = [0.39–0.65] for ESO 565-G019.

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X-Rays from Active Galactic Nuclei

Highlights of Astronomy ◽

10.1017/s1539299600005499 ◽

1983 ◽

Vol 6 ◽

pp. 491-498 ◽

Cited By ~ 1

Author(s):

A.C. Fabian

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Seyfert Galaxies ◽

X Rays ◽

Bl Lac Objects ◽

X Ray ◽

Bl Lac

Recent X-ray observations of active galactic nuclei and Seyfert galaxies in particular are briefly reviewed. The application of the efficiency limit to rapidly varying luminous sources such as NGC 6814 is discussed. It is argued that the variability and probable MeV spectral turnover imply that most of the electrons which radiate the observed flux are only mildly relativistic. A possible link between the steep soft X-ray spectra and featureless optical continua of BL Lac objects is considered.

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Sources of X-rays from galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312009039 ◽

2011 ◽

Vol 7 (S284) ◽

pp. 183-192

Author(s):

Q. Daniel Wang

Keyword(s):

Active Galactic Nuclei ◽

Galaxy Evolution ◽

Supernova Remnants ◽

Large Scale ◽

Formation Rate ◽

Galactic Nuclei ◽

High Energy ◽

High Mass ◽

X Rays ◽

X Ray

AbstractGalactic X-ray emission is a manifestation of various high-energy phenomena and processes. The brightest X-ray sources are typically accretion-powered objects: active galactic nuclei and low- or high-mass X-ray binaries. Such objects with X-ray luminosities of ≳ 1037 ergs s−1 can now be detected individually in nearby galaxies. The contributions from fainter discrete sources (including cataclysmic variables, active binaries, young stellar objects, and supernova remnants) are well correlated with the star formation rate or stellar mass of galaxies. The study of discrete X-ray sources is essential to our understanding of stellar evolution, dynamics, and end-products as well as accretion physics. With the subtraction of the discrete source contributions, one can further map out truly diffuse X-ray emission, which can be used to trace the feedback from active galactic nuclei, as well as from stars, both young and old, in the form of stellar winds and supernovae. The X-ray emission efficiency, however, is only about 1% of the energy input rate of the stellar feedback alone. The bulk of the feedback energy is most likely gone with outflows into large-scale galactic halos. Much is yet to be investigated to comprehend the role of such outflows in regulating the ecosystem, hence the evolution of galaxies. Even the mechanism of the diffuse X-ray emission remains quite uncertain. A substantial fraction of the emission cannot arise directly from optically-thin thermal plasma, as commonly assumed, and most likely originates in its charge exchange with neutral gas. These uncertainties underscore our poor understanding of the feedback and its interplay with the galaxy evolution.

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Hot Accretion Disks and the High Energy Background

Symposium - International Astronomical Union ◽

10.1017/s0074180900039292 ◽

1983 ◽

Vol 104 ◽

pp. 345-346

Author(s):

M. Kafatos ◽

Jean A. Eilek

Keyword(s):

Active Galactic Nuclei ◽

Accretion Disks ◽

Spectral Range ◽

Gamma Rays ◽

Gamma Ray ◽

Galactic Nuclei ◽

Seyfert Galaxies ◽

High Energy ◽

X Rays ◽

X Ray

The origin of the high energy (X-ray and gamma-ray) background may be attributed to discrete sources, which are usually thought to be active galactic nuclei (AGN) (cf. Rothschild et al. 1982, Bignami et al. 1979). At X-rays a lot of information has been obtained with HEAO-1 in the spectral range 2–165 keV. At gamma-rays the background has been estimated from the Apollo 15 and 16 (Trombka et al. 1977) and SAS-2 (Bignami et al. 1979) observations. A summary of some of the observations (Rothschild et al. 1982) is shown in Figure 1. The contribution of AGN to the diffuse high energy background is uncertain at X-rays although it is generally estimated to be in the 20–30% range (Rothschild et al. 1982). At gamma-rays, in the range 1–150 MeV, AGN (specifically Seyfert galaxies) could account for all the emission.

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Understanding the origin of radio outflows in Seyfert galaxies using radio polarimetry

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320003014 ◽

2019 ◽

Vol 15 (S356) ◽

pp. 247-251

Author(s):

Biny Sebastian ◽

Preeti Kharb ◽

Christopher P. O’ Dea ◽

Jack F. Gallimore ◽

Stefi A. Baum ◽

...

Keyword(s):

Magnetic Fields ◽

Radio Emission ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Seyfert Galaxy ◽

Seyfert Galaxies ◽

Starburst Galaxies ◽

Galactic Magnetic Fields ◽

5 Ghz

AbstractThe role of starburst winds versus active galactic nuclei (AGN) jets/winds in the formation of the kiloparsec scale radio emission seen in Seyferts is not yet well understood. In order to be able to disentangle the role of various components, we have observed a sample of Seyfert galaxies exhibiting kpc-scale radio emission suggesting outflows, along with a comparison sample of starburst galaxies, with the EVLA B-array in polarimetric mode at 1.4 GHz and 5 GHz. The Seyfert galaxy NGC 2639, shows highly polarized secondary radio lobes, not observed before, which are aligned perpendicular to the known pair of radio lobes. The additional pair of lobes represent an older epoch of emission. A multi-epoch multi-frequency study of the starburst-Seyfert composite galaxy NGC 3079, reveals that the jet together with the starburst superwind and the galactic magnetic fields might be responsible for the well-known 8-shaped radio lobes observed in this galaxy. We find that many of the Seyfert galaxies in our sample show bubble-shaped lobes, which are absent in the starburst galaxies that do not host an AGN.

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Probing the cool ISM in galaxies via 21 cm H i absorption

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313001014 ◽

2012 ◽

Vol 8 (S292) ◽

pp. 188-188

Author(s):

J. R. Allison ◽

E. M. Sadler ◽

S. J. Curran ◽

S. N. Reeves

Keyword(s):

Spectral Line ◽

Active Galactic Nuclei ◽

Large Scale ◽

Galactic Nuclei ◽

Host Galaxies ◽

The Galaxy ◽

Early Type Galaxy ◽

Finding Method ◽

Compact Array ◽

Cold Gas

AbstractRecent targeted studies of associated H i absorption in radio galaxies are starting to map out the location, and potential cosmological evolution, of the cold gas in the host galaxies of Active Galactic Nuclei (AGN). The observed 21 cm absorption profiles often show two distinct spectral-line components: narrow, deep lines arising from cold gas in the extended disc of the galaxy, and broad, shallow lines from cold gas close to the AGN (e.g. Morganti et al. 2011). Here, we present results from a targeted search for associated H i absorption in the youngest and most recently-triggered radio AGN in the local universe (Allison et al. 2012b). So far, by using the recently commissioned Australia Telescope Compact Array Broadband Backend (CABB; Wilson et al. 2011), we have detected two new absorbers and one previously-known system. While two of these show both a broad, shallow component and a narrow, deep component (see Fig. 1), one of the new detections has only a single broad, shallow component. Interestingly, the host galaxies of the first two detections are classified as gas-rich spirals, while the latter is an early-type galaxy. These detections were obtained using a spectral-line finding method, based on Bayesian inference, developed for future large-scale absorption surveys (Allison et al. 2012a).

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Symmetry and the Arrow of Time in Theoretical Black Hole Astrophysics

Journal of Gravity ◽

10.1155/2015/530850 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5

Author(s):

David Garofalo

Keyword(s):

Black Holes ◽

Black Hole ◽

Active Galactic Nuclei ◽

Accretion Disks ◽

Time Reversal ◽

Large Scale ◽

Galactic Nuclei ◽

Arrow Of Time ◽

Time Symmetry ◽

The Universe

While the basic laws of physics seem time-reversal invariant, our understanding of the apparent irreversibility of the macroscopic world is well grounded in the notion of entropy. Because astrophysics deals with the largest structures in the Universe, one expects evidence there for the most pronounced entropic arrow of time. However, in recent theoretical astrophysics work it appears possible to identify constructs with time-reversal symmetry, which is puzzling in the large-scale realm especially because it involves the engines of powerful outflows in active galactic nuclei which deal with macroscopic constituents such as accretion disks, magnetic fields, and black holes. Nonetheless, the underlying theoretical structure from which this accreting black hole framework emerges displays a time-symmetric harmonic behavior, a feature reminiscent of basic and simple laws of physics. While we may expect such behavior for classical black holes due to their simplicity, manifestations of such symmetry on the scale of galaxies, instead, surprise. In fact, we identify a parallel between the astrophysical tug-of-war between accretion disks and jets in this model and the time symmetry-breaking of a simple overdamped harmonic oscillator. The validity of these theoretical ideas in combination with this unexpected parallel suggests that black holes are more influential in astrophysics than currently recognized and that black hole astrophysics is a more fundamental discipline.

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Disentangling AGN and starburst activities in NGC 6240 from an X-ray perspective

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315007425 ◽

2014 ◽

Vol 10 (S312) ◽

pp. 36-38

Author(s):

Junfeng Wang

Keyword(s):

Active Galactic Nuclei ◽

Large Scale ◽

Imaging Spectroscopy ◽

Galactic Nuclei ◽

Resolving Power ◽

High Excitation ◽

X Ray ◽

Supermassive Black Hole ◽

X Ray Imaging ◽

High Temperature Gas

AbstractThe circum-nuclear region in an active galaxy is often complex with presence of high excitation gas, collimated radio outflow, and star formation activities, besides the actively accreting supermassive black hole. The unique spatial resolving power of Chandra X-ray imaging spectroscopy enables more investigations to disentangle the active galactic nuclei and starburst activities. For galaxies in the throes of a violent merging event such as NGC6240, we were able to resolve the high temperature gas surrounding its binary active black holes and discovered a large scale soft X-ray halo.

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Chemical abundances in Seyfert galaxies – V. The discovery of shocked emission outside the AGN ionization axis

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa194 ◽

2020 ◽

Vol 501 (1) ◽

pp. L54-L59

Author(s):

R A Riffel ◽

O L Dors ◽

M Armah ◽

T Storchi-Bergmann ◽

A Feltre ◽

...

Keyword(s):

Electron Temperature ◽

Active Galactic Nuclei ◽

Direct Evidence ◽

Galactic Nuclei ◽

Seyfert Galaxies ◽

Chemical Abundances ◽

Temperature Distributions ◽

Field Unit ◽

Dusty Torus ◽

Integral Field

ABSTRACT We present maps for the electron temperature in the inner kpc of three luminous Seyfert galaxies: Mrk 79, Mrk 348, and Mrk 607 obtained from Gemini Multi-Object Spectrograph-integral field unit observations at spatial resolutions of ∼110–280 pc. We study the distributions of electron temperature in active galaxies and find temperatures varying in the range from ∼8000 to $\gtrsim 30\, 000\,$K. Shocks due to gas outflows play an important role in the observed temperature distributions of Mrk 79 and Mrk 348, while standard photoionization models reproduce the derived temperature values for Mrk 607. In Mrk 79 and Mrk 348, we find direct evidence for shock ionization with overall orientation orthogonal to the ionization axis, where shocks can be easily observed as the active galactic nuclei radiation field is shielded by the nuclear dusty torus. This also indicates that even when the ionization cones are narrow, the shocks can be much wider angle.

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Numerical Studies of Astrophysical Objects at Fesenkov Astrophysical Institute (FAI)

Communications of the Byurakan Astrophysical Observatory ◽

10.52526/25792776-2018.2.1-124 ◽

2018 ◽

Vol 2 (1) ◽

pp. 124-134

Author(s):

Assylkhan Bibossinov ◽

◽

Denis Yurin ◽

Chingis Omarov ◽

◽

...

Keyword(s):

Black Hole ◽

Numerical Simulations ◽

Active Galactic Nuclei ◽

Accretion Disk ◽

Large Scale ◽

International Workshop ◽

Star Clusters ◽

Galactic Nuclei ◽

Numerical Studies ◽

Astrophysical Objects

Numerical studies of astrophysical objects are a relatively new direction in Fesenkov Astrophysical Institute (FAI) and is mainly represented by the Laboratory of Cosmology, Stellar Dynamics and Computational Astrophysics. The lab seeks to understand the evolution of gravitating systems at various scales – from star clusters to galaxies to large-scale structure of the universe as a whole, and tackles these problems both through analytical methods and through numerical simulations. The particular focus is on numerical simulations of star clusters, especially those found in active galactic nuclei – this is a topic of oldestablished collaboration with colleagues from Astronomisches Rechen-Institut (Heidelberg) and National Astronomical Observatories of China (Beijing). The prominent example is STARDISK project dedicated to the numerical research of active galactic nuclei as multicomponent systems composed of compact stellar cluster, gaseous accretion disk and a supermassive black hole. It is demonstrated that an accretion disk can noticeably decelerate stars and thus enhance the accretion rate onto the black hole. In 2013 FAI hosted the MODEST-13 International Workshop dedicated to modeling of star clusters. Recently a new project has been approved aimed at construction of triaxial equilibrium N-body systems that can be of great help in various numerical experiments with disk galaxies. There are also long standing plans to perform cosmological simulations of large scale structures to test a new approach to dark matter and energy actively developed at FAI. For numerical calculations, FAI has a small, but growing computer cluster consisting of several high-performance computing servers equipped with computational GPU cards.

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