Tracking the state transitions in changing-look active galactic nuclei through their polarized-light echoes

Context. Variations in the mass accretion rate appear to be responsible for the rapid transitions in spectral type that are observed in increasingly more active galactic nuclei (AGNs). These objects are now labeled “changing-look” AGNs and are key objects for understanding the physics of accretion onto supermassive black holes. Aims. We aim to complement the analysis and interpretation of changing-look AGNs by modeling the polarization variations that can be observed, in particular, polarized-light echoes. Methods. We built a complex and representative model of an AGN and its host galaxy and ran radiative transfer simulations to obtain realistic time-dependent polarization signatures of changing-look objects. Based on actual data, we allowed the system to become several times fainter or brighter within a few years, assuming a rapid change in accretion rate. Results. We obtain time-dependent polarization signatures of distant high-luminosity (quasars) and nearby low-luminosity (Seyferts) changing-look AGNs for a representative set of inclinations. We predict the evolution of the continuum polarization for future polarimetric campaigns with the goal to better understand the physics at work in these objects. We also investigate highly inclined AGNs that experience strong accretion rate variations without appearing to change state. We apply our modeling to Mrk 1018, the best-documented case of a changing-look AGN, and predict a variation in its polarization after the recent dimming of its continuum. Conclusions. We demonstrate that polarization monitoring campaigns that cover the transitions that are observed in changing-look AGNs might bring crucial information on the geometry and composition of all the reprocessing regions within the nucleus. In particular, specific features in the time variation of the polarization position angle can provide a new and efficient method for determining AGN inclinations.

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Line-driven disc wind in near-Eddington active galactic nuclei: decrease of mass accretion rate due to powerful outflow

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa948 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3616-3626 ◽

Cited By ~ 2

Author(s):

Mariko Nomura ◽

Ken Ohsuga ◽

Chris Done

Keyword(s):

Black Holes ◽

Mass Loss ◽

Active Galactic Nuclei ◽

Accretion Rate ◽

Galactic Nuclei ◽

Host Galaxy ◽

Radiation Hydrodynamics ◽

Iterative Technique ◽

X Ray ◽

Mass Accretion Rate

ABSTRACT Based on recent X-ray observations, ultrafast outflows from supermassive black holes are expected to have enough energy to dramatically affect their host galaxy but their launch and acceleration mechanisms are not well understood. We perform two-dimensional radiation hydrodynamics simulations of UV line-driven disc winds in order to calculate the mass-loss rates and kinetic power in these models. We develop a new iterative technique that reduces the mass accretion rate through the inner disc in response to the wind mass-loss. This makes the inner disc less UV bright, reducing the wind power compared to previous simulations which assumed a constant accretion rate with radius. The line-driven winds in our simulations are still extremely powerful, with around half the supplied mass accretion rate being ejected in the wind for black holes with mass 108–$10^{10}\, \mathrm{ M}_\odot$ accreting at L/LEdd = 0.5–0.9. Our results open up the way for estimating the growth rate of supermassive black hole and evaluating the kinetic energy ejected into the interstellar medium (active galactic nuclei feedback) based on a physical model of line-driven disc winds.

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Jet-Induced Feedback in the [O III] Lines of Early Evolution Stage Active Galactic Nuclei

Universe ◽

10.3390/universe7060188 ◽

2021 ◽

Vol 7 (6) ◽

pp. 188

Author(s):

Marco Berton ◽

Emilia Järvelä

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Plasma Jets ◽

Early Evolution ◽

Host Galaxy ◽

Bolometric Luminosity ◽

Radio Imaging ◽

Strong Relation ◽

Evolution Stage ◽

Good Proxy

It is well known that active galactic nuclei (AGN) show various forms of interaction with their host galaxy, in a number of phenomena generally called AGN feedback. In particular, the relativistic plasma jets launched by a fraction of AGN can strongly affect their environment. We present here a study of the [O III] λλ4959,5007 lines in a diverse sample of early evolution stage AGN–specifically narrow-line Seyfert 1 galaxies. Radio imaging observations of all of the sources enable a division to jetted and non-jetted sources, and exploiting this we show that the ionized gas properties are significantly influenced by the presence of the jets, as we often find the [O III] lines (blue-)shifted with respect to their restframe wavelength. We also show how the radio morphology and the radio spectral index do not seem to play a role in the origin of the [O III] shifts, thus suggesting that the source inclination is not relevant to the lines displacement. We do not find a strong relation between the [O III] line properties and the bolometric luminosity, suggesting that within our sample radiatively driven outflows do not seem to have a significant contribution to the [O III] line kinematics. We finally suggest that [O III] shifts may be a good proxy to identify the presence of relativistic jets. Additional studies, especially with integral-field spectroscopy, will provide a deeper insight into the relation between jets and their environment in early evolution stage AGN.

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Host galaxy properties of X-ray active galactic nuclei in the local Universe

Astronomy and Astrophysics ◽

10.1051/0004-6361/202142466 ◽

2021 ◽

Author(s):

L. Koutoulidis ◽

G. Mountrichas ◽

I. Georgantopoulos ◽

E. Pouliasis ◽

M. Plionis

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Host Galaxy ◽

Local Universe ◽

X Ray

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Radiative efficiency of hot accretion flow and the radio/X-ray correlation in X-ray binaries

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315007723 ◽

2014 ◽

Vol 10 (S312) ◽

pp. 139-140

Author(s):

Fu-Guo Xie

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

Accretion Rate ◽

Galactic Nuclei ◽

X Ray ◽

Radiative Efficiency ◽

Accretion Flow ◽

Accretion Rates ◽

Distinctive Property ◽

X Ray Binaries

AbstractSignificant progresses have been made since the discovery of hot accretion flow, a theory successfully applied to the low-luminosity active galactic nuclei (LLAGNs) and black hole (BH) X-ray binaries (BHBs) in their hard states. Motivated by these updates, we re-investigate the radiative efficiency of hot accretion flow. We find that, the brightest regime of hot accretion flow shows a distinctive property, i.e. it has a constant efficiency independent of accretion rates, similar to the standard thin disk. For less bright regime, the efficiency has a steep positive correlation with the accretion rate, while for faint regime typical of advection-dominated accretion flow, the correlation is shadower. This result can naturally explain the observed two distinctive correlations between radio and X-ray luminosities in black hole X-ray binaries. The key difference in systems with distinctive correlations could be the viscous parameter, which determines the critical luminosity of different accretion modes.

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Chandra COSMOS Legacy Survey: Clustering dependence of Type 2 active galactic nuclei on host galaxy properties

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936191 ◽

2019 ◽

Vol 632 ◽

pp. A88

Author(s):

V. Allevato ◽

A. Viitanen ◽

A. Finoguenov ◽

F. Civano ◽

H. Suh ◽

...

Keyword(s):

Active Galactic Nuclei ◽

Large Scale ◽

Formation Rate ◽

Galactic Nuclei ◽

Stellar Mass ◽

Host Galaxy ◽

X Ray ◽

Normal Galaxies ◽

Massive Halos

Aims. We perform clustering measurements of 800 X-ray selected Chandra COSMOS Legacy (CCL) Type 2 active galactic nuclei (AGN) with known spectroscopic redshift to probe the halo mass dependence on AGN host galaxy properties, such as galaxy stellar mass Mstar, star formation rate (SFR), and specific black hole accretion rate (BHAR; λBHAR) in the redshift range z = [0−3]. Methods. We split the sample of AGN with known spectroscopic redshits according to Mstar, SFR and λBHAR, while matching the distributions in terms of the other parameters, including redshift. We measured the projected two-point correlation function wp(rp) and modeled the clustering signal, for the different subsamples, with the two-halo term to derive the large-scale bias b and corresponding typical mass of the hosting halo. Results. We find no significant dependence of the large-scale bias and typical halo mass on galaxy stellar mass and specific BHAR for CCL Type 2 AGN at mean z ∼ 1, while a negative dependence on SFR is observed, i.e. lower SFR AGN reside in richer environment. Mock catalogs of AGN, matched to have the same X-ray luminosity, stellar mass, λBHAR, and SFR of CCL Type 2 AGN, almost reproduce the observed Mstar − Mh, λBHAR − Mh and SFR–Mh relations, when assuming a fraction of satellite AGN fAGNsat ∼ 0.15. This corresponds to a ratio of the probabilities of satellite to central AGN of being active Q ∼ 2. Mock matched normal galaxies follow a slightly steeper Mstar − Mh relation, in which low mass mock galaxies reside in less massive halos than mock AGN of similar mass. Moreover, matched mock normal galaxies are less biased than mock AGN with similar specific BHAR and SFR, at least for Q > 1.

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CHANDRAX-RAY ANDHUBBLE SPACE TELESCOPEIMAGING OF OPTICALLY SELECTED KILOPARSEC-SCALE BINARY ACTIVE GALACTIC NUCLEI. II. HOST GALAXY MORPHOLOGY AND AGN ACTIVITY

The Astrophysical Journal ◽

10.3847/0004-637x/823/1/50 ◽

2016 ◽

Vol 823 (1) ◽

pp. 50 ◽

Cited By ~ 15

Author(s):

Jinyi Shangguan ◽

Xin Liu ◽

Luis C. Ho ◽

Yue Shen ◽

Chien Y. Peng ◽

...

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Host Galaxy ◽

Galaxy Morphology

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Quasar Evolution and the Growth of Black Holes in the Nuclei of Active Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900140926 ◽

1989 ◽

Vol 134 ◽

pp. 233-239

Author(s):

R. D. Blandford

Keyword(s):

Black Holes ◽

Active Galactic Nuclei ◽

Radiation Pressure ◽

High Redshift ◽

Galactic Nuclei ◽

Rapid Decrease ◽

Active Galaxies ◽

Host Galaxy ◽

Nearby Galaxies ◽

The Mean

The observed evolutionary behavior of active galactic nuclei is compatible with a model in which black holes form in the nuclei of new-born galaxies and then grow at a rate limited by both radiation pressure and the supply of gas. Individual sources become more luminous with time as long as they are being fueled. However, the rapid decrease in the mean rate of supply of gas causes a strong decline in the space density of active objects. Nearby galaxies should harbor modest size (∼ 106 – 108 M⊙) black holes. It is suggested that the gas that fuels high redshift quasars is mostly derived from the host galaxy.

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DUST-CORRECTED COLORS REVEAL BIMODALITY IN THE HOST-GALAXY COLORS OF ACTIVE GALACTIC NUCLEI AT z ∼ 1

The Astrophysical Journal ◽

10.1088/2041-8205/721/1/l38 ◽

2010 ◽

Vol 721 (1) ◽

pp. L38-L42 ◽

Cited By ~ 73

Author(s):

Carolin N. Cardamone ◽

C. Megan Urry ◽

Kevin Schawinski ◽

Ezequiel Treister ◽

Gabriel Brammer ◽

...

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Host Galaxy

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ASYMMETRIES OF AGN JETS IN INHOMOGENEOUS MEDIA

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194514601926 ◽

2014 ◽

Vol 28 ◽

pp. 1460192

Author(s):

VOLKER GAIBLER

Keyword(s):

Interstellar Medium ◽

Active Galactic Nuclei ◽

High Redshift ◽

Galactic Nuclei ◽

Inhomogeneous Media ◽

Host Galaxy ◽

Radio Sources ◽

Propagation Models ◽

Hydrodynamical Simulations

Considerable asymmetries in jets from active galactic nuclei (AGN) and associated double radio sources can be caused by an inhomogeneous interstellar medium of the host galaxy. These asymmetries can easily be estimated by 1D propagation models, but hydrodynamical simulations have shown that the actual asymmetries can be considerably larger. With a set of smaller-scale hydrodynamical simulations we examine these asymmetries, and find they are typically a factor of ~ 3 larger than in 1D models. We conclude that, at high redshift, large asymmetries in radio sources are expected in gas-rich galaxies with a clumpy interstellar medium.

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