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The Symbiosis between Radio Source and Galaxy Evolution

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A special issue of Galaxies (ISSN 2075-4434).

Deadline for manuscript submissions: closed (30 April 2023) | Viewed by 22804

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Prof. Dr. Stefi Baum

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Guest Editor

Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
Interests: the study of activity in galaxies and its relation to galaxy evolution

Prof. Dr. Christopher P. O'Dea

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Co-Guest Editor

Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
Interests: active galactic nuclei (AGN); AGN feedback; radio galaxies; black holes; clusters of galaxies

Special Issue Information

Dear Colleagues,

Supermassive black holes located in the center of a galaxy can be fueled by infalling matter, producing extremely energetic phenomena such as luminous hot disks of accreting gas (accretion disks) and powerful outflows of relativistic plasma and magnetic fields (jets) in radio galaxies. We now know that the nuclei of a random galaxy will, statistically, contain a super-massive black hole whose mass is roughly 0.1% of the mass of the galaxy. It is has also now been shown that powerful AGN-driven outflows directly affect the evolution of galaxies, heating the galaxy's cold gas and/or expelling it from the central bulge regions. This, in turn, influences galaxies' star formation histories, mediating the relationship between host galaxy and central supermassive black hole and shaping the high luminosity end of the galaxy luminosity function. This process has been dubbed AGN Feedback and points to a direct link between nuclear activity (which occurs when the black hole is growing via accretion) and star formation and matter accretion (which occurs when the galaxy is growing). The growth of the central engine and the evolution of the galaxy are linked in a symbiotic relationship impacting their co-evolution. While AGN feedback is now routinely incorporated into hydrodynamical simulations of galaxy evolution, major uncertainties remain. We are yet to understand in detail how AGN interact with the forming and evolving host galaxies, and how the host galaxy and its evolution impacts the central black hole. In order to elucidate this fundamental process of energy exchange and growth that has shaped our universe's evolution, in this volume we will explore the physics behind the co-evolution of central massive black holes and galaxy formation in radio galaxies.

Prof. Dr. Stefi Baum
Prof. Dr. Christopher P. O'Dea
Guest Editors

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Keywords

AGN feedback
radio galaxies
massive black holes
galaxy evolution

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Published Papers (10 papers)

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Editorial

Jump to: Research, Review

5 pages, 3685 KiB

Open AccessEditorial

The Revised Third Cambridge Catalogue at 60: To Jet or Not to Jet …

by Peter Barthel and Paolo Padovani

Galaxies 2024, 12(1), 3; https://doi.org/10.3390/galaxies12010003 - 11 Jan 2024

Viewed by 1710

Abstract

The Revised Third Cambridge Catalogue of Radio Sources (in the northern sky), or 3CR, published sixty years ago by Bennett (1962) [...] Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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Research

Jump to: Editorial, Review

29 pages, 1159 KiB

Open AccessArticle

A Walk through AGN Country—For the Somewhat Initiated!

by Robert R. J. Antonucci

Galaxies 2023, 11(5), 102; https://doi.org/10.3390/galaxies11050102 - 30 Sep 2023

Cited by 6 | Viewed by 1751

Abstract

Key issues in AGN and galaxy formation are discussed. Very successful Unified Models explain much of the variety of AGN with orientation effects; the ingredients are shadowing by a dusty “torus” and relativistic beaming. A spinoff result is described which is important for the formation of massive elliptical galaxies, the most spectacular and unequivocal AGN feedback phenomenon known. This is the so-called “alignment effect” in powerful radio galaxies at

z \overset{>}{\sim} 1

. One of them is a BAL radio galaxy! Next, I explain a very robust derivation of the reddening law for nuclear dust, which reveals a dearth of small grains on parsec scales. Then, the quasistatic thin accretion disk model, thought by many to explain the energetically dominant optical/UV continuum, is thoroughly debunked. Much of this was known when the model was proposed 35 years ago. A new argument is provided that trivially falsifies a huge superset of such models. I then show that it is possible to see the central engine spectrum with the atomic and dust emission surgically removed! Few have noticed this breakthrough work. Finally, the far IR dust emission in Cygnus A is 10% polarized; to date, high nuclear dust polarization has been seen in all radio loud objects and no radio quiet ones. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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14 pages, 906 KiB

Open AccessArticle

Intermediate-Mass Black Holes: The Essential Population to Explore the Unified Model for Accretion and Ejection Processes

by Xiaolong Yang and Jun Yang

Galaxies 2023, 11(2), 53; https://doi.org/10.3390/galaxies11020053 - 6 Apr 2023

Cited by 3 | Viewed by 2197

Abstract

We study radio and X-ray emissions from intermediate-mass black holes (IMBHs) and explore the unified model for accretion and ejection processes. The radio band survey of IMBH (candidate) hosted galaxies indicates that only a small fraction (∼0.6%) of them are radio-band active. In addition, very long baseline interferometry observations reveal parsec-scale radio emission of IMBHs, further resulting in a lower fraction of actively ejecting objects (radio emission is produced by IMBHs other than hosts), which is consistent with a long quiescent state in the evolution cycle of IMBHs. Most (75%, i.e., 3 out of 4 samples according to a recent mini-survey) of the radio-emitting IMBHs are associated with radio relics and there is also evidence of dual radio blobs from episodic ejecting phases. Taking the radio emission and the corresponding core X-ray emission of IMBH, we confirm a universal fundamental plane relation (FMP) of black hole activity. Furthermore, state transitions can be inferred by comparing a few cases in XRBs and IMBHs in FMP, i.e., both radio luminosity and emission regions evolve along these state transitions. These signatures and evidence suggest an analogy among all kinds of accretion systems which span from stellar mass to supermassive black holes, hinting at unified accretion and ejection physics. To validate the unified model, we explore the correlation between the scale of outflows (corresponding to ejection powers) and the masses of central engines; it shows that the largest scale of outflows

{\hat{L S}}_{out}

follows a power-law correlation with the masses of accretors

M_{core}

, i.e.,

log {\hat{L S}}_{out} = (0.73 \pm 0.01) log M_{core} - (3.34 \pm 0.10)

. In conclusion, this work provides evidence to support the claim that the ejection (and accretion) process behaves as scale-invariant and their power is regulated by the masses of accretors. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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12 pages, 1787 KiB

Open AccessFeature PaperArticle

High-Frequency and High-Resolution VLBI Observations of GHz Peaked Spectrum Objects

by Xiaopeng Cheng, Tao An, Ailing Wang and Sumit Jaiswal

Galaxies 2023, 11(2), 42; https://doi.org/10.3390/galaxies11020042 - 7 Mar 2023

Cited by 3 | Viewed by 2085

Abstract

Observational studies of GHz peaked spectrum (GPS) sources contribute to the understanding of the radiative properties and interstellar environment of host galaxies. We present the results from the multi-frequency high-resolution VLBI observations of a sample of nine GPS sources at 8, 15, and 43 GHz. All sources show core-jet structure. Four sources show relativistic jets with Doppler boosting factors ranging from 2.0 to 5.0 and a jet viewing angle between 10° and 30°. The core brightness temperatures of the other five sources are below the equipartition brightness temperature limit with their jet viewing angles in the range of 13.6° to 71.9°, which are systematically larger than those of relativistic jets in this sample. The sources show diverse variability properties, with variability levels ranging from 0.11 to 0.56. The measured turnover frequency in the radio spectrum ranges from 6.2 and 31.8 GHz (in the source’s rest frame). We estimate the equipartition magnetic field strength to be between 9 and 48 mG. These results strongly support the notion that these GPS sources are young radio sources in the very early stage of their evolution. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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19 pages, 2214 KiB

Open AccessArticle

Young Radio Sources Expanding in Gas-Rich ISM: Using Cold Molecular Gas to Trace Their Impact

by Raffaella Morganti, Suma Murthy, Pierre Guillard, Tom Oosterloo and Santiago Garcia-Burillo

Galaxies 2023, 11(1), 24; https://doi.org/10.3390/galaxies11010024 - 2 Feb 2023

Cited by 8 | Viewed by 2152

Abstract

We present an overview of the results obtained from the study of the resolved distribution of molecular gas around eight young (

≲ 10^{6} yr

), peaked-spectrum radio galaxies. Tracing the distribution and kinematics of the gas around these radio sources allows [...] Read more.

We present an overview of the results obtained from the study of the resolved distribution of molecular gas around eight young (

≲ 10^{6} yr

), peaked-spectrum radio galaxies. Tracing the distribution and kinematics of the gas around these radio sources allows us to trace the interplay between the jets and the surrounding medium. For three of these sources, we present new CO(1-0) observations, obtained with the Northern Extended Millimeter Array (NOEMA) with arcsecond resolution. In two of these targets, we also detected CN lines, both in emission and absorption. Combining the new observations with already published data, we discuss the main results obtained. Although we found that a large fraction of the cold molecular gas was distributed in disc-like rotating structures, in the vast majority of the sources, high turbulence and deviations from purely quiescent gas (including outflows) were observed in the region co-spatial with the radio continuum emission. This suggests the presence of an interaction between radio plasma and cold molecular gas. In particular, we found that newly born and young radio jets, even those with low power i.e., P_jet < 10⁴⁵ erg s⁻¹), are able to drive massive outflows of cold, molecular gas. The outflows are, however, limited to the sub-kpc regions and likely short lived. On larger scales (a few kpc), we observed cases where the molecular gas appears to avoid the radio lobes and, instead, wraps around them. The results suggest the presence of an evolutionary sequence, which is consistent with previous simulations, where the type of impact of the radio plasma changes as the jet expands, going from a direct jet-cloud interaction able to drive gas outflows on sub-kpc scales to a more gentle pushing aside of the gas, increasing its turbulence and likely limiting its cooling on kpc scales. This effect can be mediated by the cocoon of shocked gas inflated by the jet–cloud interactions. Building larger samples of young and evolved radio sources for observation at a similar depth and spatial resolution to test this scenario is now needed and may be possible thanks to more data becoming available in the growing public archives. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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10 pages, 1221 KiB

Open AccessArticle

A Global Inventory of Feedback

by Timothy M. Heckman and Philip N. Best

Galaxies 2023, 11(1), 21; https://doi.org/10.3390/galaxies11010021 - 24 Jan 2023

Cited by 15 | Viewed by 1937

Abstract

Feedback from both supermassive black holes and massive stars plays a fundamental role in the evolution of galaxies and the inter-galactic medium. In this paper, we use available data to estimate the total amount of kinetic energy and momentum created per co-moving volume element over the history of the universe from three sources: massive stars and supernovae, radiation pressure and winds driven by supermassive black holes, and radio jets driven by supermassive black holes. Kinetic energy and momentum injection from jets peaks at z ≈ 1, while the other two sources peak at z ≈ 2. Massive stars are the dominant global source of momentum injection. For supermassive black holes, we find that the amount of kinetic energy from jets is about an order-of-magnitude larger than that from winds. We also find that the amount of kinetic energy created by massive stars is about 2.5 ε_star times that carried by jets (where ε_star is the fraction of injected energy not lost to radiative cooling). We discuss the implications of these results for the evolution of galaxies and IGM. Because the ratio of the black hole mass to galaxy mass is a steeply increasing function of mass, we show that the relative importance of black hole feedback to stellar feedback likewise increases with mass. We show that there is a trend in the present-day universe which, in the simplest picture, is consistent with galaxies that have been dominated by black hole feedback being generally quenched, while galaxies that have been dominated by stellar feedback are star-forming. We also note that the amount of kinetic energy carried by jets and winds appears to be sufficient to explain the properties of hot gas in massive halos (>10¹³ M_ʘ). Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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Review

Jump to: Editorial, Research

22 pages, 3833 KiB

Open AccessReview

What Drives the Ionized Gas Outflows in Radio-Quiet AGN?

by Mainak Singha, Christopher P. O’Dea and Stefi A. Baum

Galaxies 2023, 11(4), 85; https://doi.org/10.3390/galaxies11040085 - 12 Jul 2023

Cited by 5 | Viewed by 2462

Abstract

We review the mechanisms driving the ionized gas outflows in radio-quiet (RQ) AGN. Although it constitutes ∼90% of the AGN population, what drives these outflows in these AGNs remains an open question. High-resolution imaging and integral field unit (IFU) observation is key to spatially resolving these outflows, whereas radio observations are important to comprehend the underlying radiative processes. Radio interferometric observations have detected linear, collimated structures on the hundreds of pc scale in RQ AGN, which may be very similar to the extended radio jets in powerful galaxies. Proper motions measured in some objects are sub-relativistic. Other processes, such as synchrotron radiation from shock-accelerated gas around the outflows could give rise to radio emissions as well. Near the launching region, these outflows may be driven by the thermal energy of the accretion disk and exhibit free–free emission. IFU observations on the other hand have detected evidence of both winds and jets and the outflows driven by them in radio-quiet AGN. Some examples include nearby AGN such as Mrk 1044 and HE 1353-1917. An IFU study of nearby (z

< 0.06

) RQ AGN has found that these outflows may be related to their radio properties on <100 pc scale, rather than their accretion properties. Recent JWST observations of RQ AGN XID 2028 have revealed that radio jets and wind could inflate bubbles, create cavities, and trigger star formation. Future high-resolution multi-wavelength observations and numerical simulations taking account of both jets and winds are hence essential to understand the complex interaction between radio-quiet AGN and the host from sub-pc to kpc scales. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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21 pages, 16327 KiB

Open AccessReview

The Interplay between Radio AGN Activity and Their Host Galaxies

by Guilherme S. Couto and Thaisa Storchi-Bergmann

Galaxies 2023, 11(2), 47; https://doi.org/10.3390/galaxies11020047 - 21 Mar 2023

Cited by 6 | Viewed by 2248

Abstract

Radio activity in AGN (Active Galactic Nuclei) produce feedback on the host galaxy via the impact of the relativistic jets on the circumnuclear gas. Although radio jets can reach up to several times the optical radius of the host galaxy, in this review we focus on the observation of the feedback deposited locally in the central region of the host galaxies, in the form of outflows due to the jet-gas interaction. We begin by discussing how galaxy mergers and interactions are the most favored scenario for triggering radio AGN after gas accretion to the nuclear supermassive black hole and star formation enhancement in the nuclear region, observed in particular in the most luminous sources. We then discuss observational signatures of the process of jet-gas coupling, in particular the resulting outflows and their effects on the host galaxy. These include the presence of shock signatures and the detection of outflows not only along the radio jet but perpendicular to it in many sources. Although most of the studies are done via the observation of ionized gas, molecular gas is also being increasingly observed in outflow, contributing to the bulk of the mass outflow rate. Even though most radio sources present outflow kinetic powers that do not reach

1 % L_{b o l}

, and thus do not seem to provide an immediate impact on the host galaxy, they act to heat the ISM gas, preventing star formation, slowing the galaxy mass build-up process and limiting the stellar mass growth, in a “maintenance mode” feedback. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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15 pages, 6010 KiB

Open AccessReview

Jet Feedback in Star-Forming Galaxies

by Martin G. H. Krause

Galaxies 2023, 11(1), 29; https://doi.org/10.3390/galaxies11010029 - 12 Feb 2023

Cited by 4 | Viewed by 2720

Abstract

In this paper, I review our understanding of how jet feedback works in star-forming galaxies. There are some interesting differences to radiative feedback from Active Galactic Nuclei (AGN). Jets act on galaxy haloes as well as on dense gas, for example in regularly rotating discs, where they can suppress star formation (particularly in the centre, negative feedback), but also enhance it (positive feedback). Jet feedback may produce turbulent, multi-phase gas structures where shocks contribute to the ionisation and is observed in connection with galactic outflows. The exact driving mechanism of these outflows is still unclear, but may be a combination of effects linked to star formation, jet-induced turbulence and radiative AGN feedback. Supermassive black holes in any galaxy can produce jets. Preferential radio detections in more massive galaxies can be explained with different conditions in the circumgalactic medium and, correspondingly, different jet–environment interactions. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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17 pages, 1456 KiB

Open AccessReview

Looking for Signatures of AGN Feedback in Radio-Quiet AGN

by Preeti Kharb and Sasikumar Silpa

Galaxies 2023, 11(1), 27; https://doi.org/10.3390/galaxies11010027 - 8 Feb 2023

Cited by 8 | Viewed by 2223

Abstract

In this article, we discuss the state of “AGN feedback” in radio-quiet (RQ) AGN. This study involves heterogeneous samples of nearby Seyfert and LINER galaxies as well as quasi-stellar objects (QSOs) that have been observed at low radio frequencies (few ∼100 MHz) with the upgraded Giant Meterwave Radio Telescope (GMRT) and ∼GHz frequencies with the Karl G. Jansky Very Large Array (VLA) and Very Long Baseline Array (VLBA). These multi-frequency, multi-resolution observations detect a range of arcsecond-scale radio spectral indices that are consistent with the presence of multiple contributors including starburst winds and AGN jets or winds; steep spectrum “relic” emission is observed as well. Polarization-sensitive data from the VLA and GMRT suggest that the radio outflows are stratified (e.g., in IIIZw2, Mrk231); distinct polarization signatures suggest that there could either be a “spine + sheath” structure in the radio outflow, or there could be a “jet + wind” structure. Similar nested biconical outflows can also explain the VLBA and SDSS emission-line data in the KISSR sample of double-peaked emission-line Seyfert and LINER galaxies. Furthermore, the modeling of the emission-lines with plasma modeling codes such as MAPPINGS indicates that parsec-scale jets and winds in these sources can disturb or move the narrow-line region (NLR) gas clouds via the “shock + precursor” mechanism. Apart from the presence of “relic” emission, several Seyfert and LINER galaxies show clear morphological signatures of episodic jet activity. In one such source, NGC2639, at least four distinct episodes of jets are observed, the largest one of which was only detectable at 735 MHz with the GMRT. Additionally, a ∼6 kpc hole in the CO molecular gas along with a dearth of young stars in the center of its host galaxy is observed. Multiple jet episodes on the 10–100 parsec scales and a ∼10 parsec hole in the molecular gas is also observed in the Seyfert galaxy NGC4051. This suggests a link between episodic jet activity in RQ AGN and “AGN feedback” influencing the evolution of their host galaxies. However, a similar simple relationship between radio outflows and molecular gas mass is not observed in the Palomar–Green (PG) QSO sample, indicating that “AGN feedback” is a complex phenomenon in RQ AGN. “AGN feedback” must occur through the local impact of recurring multi-component outflows in RQ AGN. However, global feedback signatures on their host galaxy properties are not always readily evident. Full article

(This article belongs to the Special Issue The Symbiosis between Radio Source and Galaxy Evolution)

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