Simulations of Galactic Outflows Driven by Active Galactic Nuclei and Starbursts

  • Abstract
  • Literature Map
  • References
  • Similar Papers
Abstract
Translate article icon Translate Article Star icon
Take notes icon Take Notes

Abstract Using the hydro code Athena++, we run a series of large-scale hydrodynamic simulations of galactic outflows on a scale of ∼5 kpc scale over a time period of 5 Myr. We compare the kinematics, composition, and simulated X-ray emission of starburst (SB) versus active galactic nuclei (AGN) dominated galactic outflows. Our set of simulations includes galactic outflows driven solely by a nuclear SB, an AGN wind, and a mixture of SBs and AGN winds. We find significant differences in the kinematics, composition, and simulated X-ray emission between SB- versus AGN-dominated outflows. Starburst-driven outflows are characterized by turbulent, multiphase, complex flows, with each phase having a distinct kinematic profile (as traced by various oxygen ions), while AGN-driven outflows are more symmetric, more single phase, with primarily very hot (>107 K) gas, and are smooth in appearance. In mixed SB-AGN simulations, the dominant component (SB or AGN) determines the outflow characteristics. In cases where the energy input of the SB is similar to the energy of the AGN, the resulting outflow appears similar to the SB-only outflow, but when the energy input from the AGN wind is much greater than the SB then the outflow appears similar to the AGN-only outflow. When we generate synthetic X-ray observations, the AGN-dominated outflows are essentially invisible in soft to medium-energy X-rays (0.1–10.0 keV), but the SB-driven outflows show complex filamentary structures that are visible in the X-ray. Finally, we show the observational possibilities for various proposed and future X-ray telescopes.

ReferencesShowing 10 of 77 papers
  • Open Access Icon
  • Cite Count Icon 427
  • 10.3847/1538-4365/ab929b
The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers
  • Jun 25, 2020
  • The Astrophysical Journal Supplement Series
  • James M Stone + 3 more

  • Open Access Icon
  • Cite Count Icon 429
  • 10.1111/j.1365-2966.2012.21512.x
The physics of galactic winds driven by active galactic nuclei
  • Jul 30, 2012
  • Monthly Notices of the Royal Astronomical Society
  • Claude-André Faucher-Giguère + 1 more

  • Open Access Icon
  • Cite Count Icon 100
  • 10.1111/j.1365-2966.2009.14860.x
Constraints on turbulent pressure in the X-ray haloes of giant elliptical galaxies from resonant scattering
  • Aug 4, 2009
  • Monthly Notices of the Royal Astronomical Society
  • N Werner + 7 more

  • Open Access Icon
  • Cite Count Icon 16
  • 10.1093/pasj/psae080
The XRISM first-light observation: Velocity structure and thermal properties of the supernova remnant N 132D
  • Oct 10, 2024
  • Publications of the Astronomical Society of Japan
  • Jelle Kaastra + 99 more

  • Open Access Icon
  • Cite Count Icon 9
  • 10.1093/mnras/stac2759
Simulations of black hole fueling in isolated and merging galaxies with an explicit, multiphase ISM
  • Oct 3, 2022
  • Monthly Notices of the Royal Astronomical Society
  • Aneesh Sivasankaran + 11 more

  • Open Access Icon
  • Cite Count Icon 95
  • 10.1086/118342
The Complex X-Ray Spectra of M82 and NGC 253
  • Apr 1, 1997
  • The Astronomical Journal
  • A Ptak + 4 more

  • Open Access Icon
  • Cite Count Icon 3
  • 10.3847/1538-4357/aba26f
Massive Galaxies Impede Massive Outflows
  • Aug 1, 2020
  • The Astrophysical Journal
  • Ryan Tanner

  • Cite Count Icon 1
  • 10.1002/asna.202023781
Lessons learned from 19 years of high‐resolution X‐ray spectroscopy of galaxy clusters with the reflection grating spectrometer on board XMM‐Newton
  • Feb 1, 2020
  • Astronomische Nachrichten
  • Ciro Pinto + 3 more

  • Open Access Icon
  • Cite Count Icon 14
  • 10.1093/pasj/61.5.1099
Origin of Thermal and Non-Thermal Hard X-Ray Emission from the Galactic Center
  • Oct 25, 2009
  • Publications of the Astronomical Society of Japan
  • Vladimir A Dogiel + 12 more

  • Open Access Icon
  • Cite Count Icon 31
  • 10.1051/0004-6361/201833860
X-ray spectra of the Fe-L complex
  • Jul 1, 2019
  • Astronomy & Astrophysics
  • Liyi Gu + 9 more

Similar Papers
  • Research Article
  • Cite Count Icon 6
  • 10.1093/mnras/stac2614
What powers galactic outflows: nuclear starbursts or AGN?
  • Sep 17, 2022
  • Monthly Notices of the Royal Astronomical Society
  • W Ishibashi + 1 more

Galactic outflows can be powered either by nuclear starbursts (SB) or active galactic nuclei (AGNs). It has been argued that extreme starbursts can power extreme outflows, without the need to invoke AGN feedback. However, contributions from past and/or hidden AGN activity cannot be ruled out. Here, we constrain the potential role of the central black hole in driving powerful outflows in starburst galaxies (with no sign of ongoing AGN activity). We examine whether the galactic outflows can be explained by AGN luminosity evolution in the framework of our AGN ‘radiative dusty feedback’ scenario. We show that the outflow energetics of starburst galaxies in the local Universe can be quantitatively reproduced by power-law and exponential luminosity decays, coupled with radiation trapping. Likewise, a combination of heavy obscuration and mild luminosity decay may account for the energetics of galactic outflows observed in dusty star-forming galaxies in the early Universe. We discuss different physical arguments for SB versus AGN outflow-driving, and conclude that the latter can have a major impact on the evolution of galaxies.

  • Research Article
  • Cite Count Icon 111
  • 10.1111/j.1365-2966.2011.20187.x
Galaxy-scale outflows driven by active galactic nuclei
  • Dec 30, 2011
  • Monthly Notices of the Royal Astronomical Society
  • Jackson Debuhr + 2 more

We present hydrodynamical simulations of major mergers of galaxies and study the effects of winds produced by active galactic nuclei (AGN) on interstellar gas in the AGN’s host galaxy. We consider winds with initial velocities ∼10 000 km s−1 and an initial momentum (energy) flux of ∼τw L/c (∼ 0.01 τw L), with ⁠. The AGN wind sweeps up and shock heats the surrounding interstellar gas, leading to a galaxy-scale outflow with velocities ∼1000 km s−1, peak mass outflow rates comparable to the star formation rate and a total ejected gas mass of ∼3 × 109 M⊙. Large momentum fluxes, τw≳ 3, are required for the AGN-driven galactic outflow to suppress star formation and accretion in the black hole’s host galaxy. Less powerful AGN winds (τw≲ 3) still produce a modest galaxy-scale outflow, but the outflow has little global effect on the ambient interstellar gas. We argue that this mechanism of AGN feedback can plausibly produce the high-velocity outflows observed in post-starburst galaxies and the massive molecular and atomic outflows observed in local ultraluminous infrared galaxies. Moreover, the outflows from local ultraluminous infrared galaxies are inferred to have τw∼ 10, comparable to what we find is required for AGN winds to regulate the growth of black holes and set the MBH - σ relation. We conclude by discussing theoretical mechanisms that can lead to AGN wind mass loading and momentum/energy fluxes large enough to have a significant impact on galaxy formation.

  • Research Article
  • Cite Count Icon 25
  • 10.1051/0004-6361/201833706
Probing the nature and origin of dust in the reddened quasar IC 4329A with global modelling from X-ray to infrared
  • Nov 1, 2018
  • Astronomy & Astrophysics
  • Missagh Mehdipour + 1 more

Cosmic dust is a key tracer of structure formation and evolution in the universe. In active galactic nuclei (AGN) the origin and role of dust are uncertain. Here, we have studied dust in the X-ray bright and reddened type-1 quasar IC 4329A, which exhibits an ionised AGN wind. We incorporated high-resolution X-ray and mid-IR spectroscopy, combined with broad-band continuum modelling, to investigate the properties of dust in this AGN. We used new chandra HETGS observations taken in June 2017, as well as archival data from XMM-Newton, Swift, HST, Spitzer, IRAS, and Herschel for our IR-optical-UV-X-ray modelling. Two distinct components of dust in IC 4329A are found. One component is in the interstellar medium (ISM) of the host galaxy, and the other is a nuclear component in the AGN torus and its associated wind. The emitting dust in the torus is evident in mid-IR emission (9.7 and 18 μm features), while dust in the wind is present through both reddening and X-ray absorption (O, Si, and Fe edge features). The gas depletion factors into dust for O, Si, and Fe are measured. We derive an intrinsic reddening E(B – V) ≈ 1.0, which is most consistent with a grey (flat) extinction law. The AGN wind consists of three ionisation components. From analysis of long-term changes in the wind, we determine limits on the location of the wind components. The two lowest ionisation components are likely carriers of dust from the AGN torus. We find that the dust in the nuclear component of IC 4329A is different from dust in the Milky Way. The dust grains in the AGN torus and wind are likely larger than the standard Galactic dust, and are in a porous composite form (containing amorphous silicate with iron and oxygen). This can be a consequence of grain coagulation in the dense nuclear environment of the AGN.

  • Research Article
  • Cite Count Icon 23
  • 10.1051/0004-6361/202039702
Physics of ULIRGs with MUSE and ALMA: The PUMA project
  • Feb 1, 2021
  • Astronomy & Astrophysics
  • M Perna + 10 more

Context. Ultraluminous infrared galaxies (ULIRGs) are characterised by extreme starburst (SB) and active galactic nucleus (AGN) activity, and are therefore ideal laboratories for studying the outflow phenomena and their feedback effects. We have recently started a project called Physics of ULIRGs with MUSE and ALMA (PUMA), which is a survey of 25 nearby (z < 0.165) ULIRGs observed with the integral field spectrograph MUSE and the interferometer ALMA. This sample includes systems with both AGN and SB nuclear activity in the pre- and post-coalescence phases of major mergers. Aims. The main goals of the project are (i) to study the prevalence of (ionised, neutral, and molecular) outflows as a function of the galaxy properties, (ii) to constrain the driving mechanisms of the outflows (e.g. distinguish between SB and AGN winds), and (iii) to identify and characterise feedback effects on the host galaxy. In this first paper, we present details on the sample selection, MUSE observations, and data reduction, and derive first high-level data products. Methods. MUSE data cubes were analysed to study the dynamical status of each of the 21 ULIRGs observed so far, taking the stellar kinematics and the morphological properties inferred from MUSE narrow-band images into account. We also located the ULIRG nuclei, taking advantage of near-infrared (HST) and millimeter (ALMA) data, and studied their optical spectra to infer (i) the ionisation state through standard optical line ratio diagnostics, and (ii) outflows in both atomic ionised ([O III], Hα) and neutral (Na ID) gas. Results. We show that the morphological and stellar kinematic classifications are consistent: post-coalescence systems are more likely associated with ordered motions, while interacting (binary) systems are dominated by non-ordered and streaming motions. We also find broad and asymmetric [O III] and Na ID profiles in almost all nuclear spectra, with line widths in the range [300 − 2000] km s−1, possibly associated with AGN- and SB-driven winds. This result reinforces previous findings that indicated that outflows are ubiquitous during the pre- and post-coalescence phases of major mergers.

  • Research Article
  • Cite Count Icon 33
  • 10.1051/0004-6361/201832604
Multi-wavelength campaign on NGC 7469
  • Jul 1, 2018
  • Astronomy & Astrophysics
  • M Mehdipour + 17 more

We investigate the physical structure of the active galactic nucleus (AGN) wind in the Seyfert-1 galaxy NGC 7469 through high-resolution X-ray spectroscopy with Chandra HETGS and photoionisation modelling. Contemporaneous data from Chandra, HST, and Swift are used to model the optical-UV-X-ray continuum and determine the spectral energy distribution (SED) at two epochs, 13 yr apart. For our investigation we use new observations taken in December 2015–January 2016, and historical ones taken in December 2002. We study the impact of a change in the SED shape, seen between the two epochs, on the photoionisation of the wind. The HETGS spectroscopy shows that the AGN wind in NGC 7469 consists of four ionisation components, with their outflow velocities ranging from − 400 to − 1800 km s-1. From our modelling we find that the change in the ionising continuum shape between the two epochs results in some variation in the ionisation state of the wind components. However, for the main ions detected in X-rays, the sum of their column densities over all components remains in practice unchanged. For two of the four components, which are found to be thermally unstable in both epochs, we obtain 2 < r < 31 pc and 12 < r < 29 pc using the cooling and recombination timescales. For the other two thermally stable components, we obtain r < 31 pc and r < 80 pc from the recombination timescale. The results of our photoionisation modelling and thermal stability analysis suggest that the absorber components in NGC 7469 are consistent with being a thermally driven wind from the AGN torus. Finally, from analysis of the zeroth-order ACIS/HETG data, we discover that the X-ray emission in the range 0.2–1 keV is spatially extended over 1.5–12′′. This diffuse soft X-ray emission is explained by coronal emission from the nuclear starburst ring in NGC 7469. The star formation rate inferred from this diffuse soft X-ray emission is consistent with those found by far-infrared studies of NGC 7469.

  • Research Article
  • 10.1051/0004-6361/202451187
The complex effect of gas cooling and turbulence on AGN-driven outflow properties
  • Nov 1, 2024
  • Astronomy & Astrophysics
  • K Zubovas + 2 more

Context. Accretion onto supermassive black holes at close to the Eddington rate is expected to drive powerful winds, which have the potential to majorly influence the properties of the host galaxy. Theoretical models of such winds can simultaneously explain observational correlations between supermassive black holes and their host galaxies, such as the M − σ relation, and the powerful multi-phase outflows that are observed in a number of active galaxies. Analytic models developed to understand these processes usually assume simple galaxy properties, namely spherical symmetry and a smooth gas distribution with an adiabatic equation of state. However, the interstellar medium in real galaxies is clumpy and cooling is important, complicating the analysis. Aims. We wish to determine how gas turbulence, uneven density distribution, and cooling influence the development of active galactic nucleus (AGN) wind-driven outflows and their global properties on kiloparsec scales. Methods. We calculated a suite of idealised hydrodynamical simulations of AGN outflows designed to isolate the effects of turbulence and cooling, both separately and in combination. All simulations initially consisted of a 1 kpc gas shell with an AGN in the centre. We measured the main outflow parameters – the velocity, the mass outflow rate (Ṁout), and the momentum (ṗoutc/LAGN) and energy (Ėout/LAGN) loading factors – as the system evolves over 1.2 Myr and estimated plausible observationally derived values. Results. We find that adiabatic simulations approximately reproduce the analytical estimates of outflow properties independently of the presence or absence of turbulence and clumpiness. Cooling, on the other hand, has a significant effect, reducing the outflow energy rate by one to two orders of magnitude in the smooth simulations and by up to one order of magnitude in the turbulent ones. The interplay between cooling and turbulence depends on AGN luminosity: in Eddington-limited AGN, turbulence enhances the coupling between the AGN wind and the gas, while in lower-luminosity simulations, the opposite is true. This mainly occurs because dense gas clumps are resilient to low-luminosity AGN feedback but get driven away by high-luminosity AGN feedback. The overall properties of multi-phase outflowing gas in our simulations qualitatively agree with observations of multi-phase outflows, although there are some quantitative differences. We also find that using ‘observable’ outflow properties leads to their parameters being underestimated by a factor of a few compared with real values. Conclusions. We conclude that the AGN wind-driven outflow model is capable of reproducing realistic outflow properties in close-to-realistic galaxy setups and that the M − σ relation can be established without efficient cooling of the shocked AGN wind. Furthermore, we suggest ways to improve large-scale numerical simulations by accounting for the effects of AGN wind.

  • Research Article
  • Cite Count Icon 53
  • 10.1093/mnras/staa2222
The impact of AGN wind feedback in simulations of isolated galaxies with a multiphase ISM
  • Aug 10, 2020
  • Monthly Notices of the Royal Astronomical Society
  • Paul Torrey + 8 more

Accreting black holes can drive fast and energetic nuclear winds that may be an important feedback mechanism associated with active galactic nuclei (AGN). In this paper, we implement a scheme for capturing feedback from these fast nuclear winds and examine their impact in simulations of isolated disc galaxies. Stellar feedback is modelled using the Feedback In Realistic Environments (fire) physics and produces a realistic multiphase interstellar medium (ISM). We find that AGN winds drive the formation of a low-density, high-temperature central gas cavity that is broadly consistent with analytic model expectations. The effects of AGN feedback on the host galaxy are a strong function of the wind kinetic power and momentum. Low- and moderate-luminosity AGN do not have a significant effect on their host galaxy: the AGN winds inefficiently couple to the ambient ISM and instead a significant fraction of their energy vents in the polar direction. For such massive black holes, accretion near the Eddington limit can have a dramatic impact on the host galaxy ISM: if AGN wind feedback acts for ≳20–30 Myr, the inner ∼1–10 kpc of the ISM is disrupted and the global galaxy star formation rate is significantly reduced. We quantify the properties of the resulting galaxy-scale outflows and find that the radial momentum in the outflow is boosted by a factor of ∼2–3 relative to that initially supplied in the AGN wind for strong feedback scenarios, decreasing below unity for less energetic winds. In contrast to observations, however, the outflows are primarily hot, with very little atomic or molecular gas. We conjecture that merging galaxies and high-redshift galaxies, which have more turbulent and thicker discs and very different nuclear gas geometries, may be even more disrupted by AGN winds than found in our simulations.

  • Research Article
  • Cite Count Icon 8
  • 10.1093/mnras/stad2460
Dust dynamics in AGN winds: a new mechanism for multiwavelength AGN variability
  • Aug 17, 2023
  • Monthly Notices of the Royal Astronomical Society
  • Nadine H Soliman + 1 more

Partial dust obscuration in active galactic nuclei (AGNs) has been proposed as a potential explanation for some cases of AGN variability. The dust–gas mixture present in AGN tori is accelerated by radiation pressure, leading to the launching of an AGN wind. Dust under these conditions has been shown to be unstable to a generic class of fast-growing resonant drag instabilities (RDIs). In this work, we present the first numerical simulations of radiation-driven outflows that explicitly include dust dynamics in conditions resembling AGN winds. We investigate the implications of RDIs on the torus morphology, AGN variability, and the ability of radiation to effectively launch a wind. We find that the RDIs rapidly develop, reaching saturation at times much shorter than the global time-scales of the outflows, resulting in the formation of filamentary structure on box-size scales with strong dust clumping and super-Alfvénic velocity dispersions. The instabilities lead to fluctuations in dust opacity and gas column density of 10–20 per cent when integrated along mock observed lines of sight to the quasar accretion disc. These fluctuations occur over year to decade time-scales and exhibit a red-noise power spectrum commonly observed for AGNs. Additionally, we find that the radiation effectively couples with the dust–gas mixture, launching highly supersonic winds that entrain 70–90 per cent of the gas, with a factor of ≲3 photon momentum loss relative to the predicted multiple-scattering momentum loading rate. Therefore, our findings suggest that RDIs play an important role in driving the clumpy nature of AGN tori and generating AGN variability consistent with observations.

  • Research Article
  • Cite Count Icon 1
  • 10.1093/mnras/stae1816
AGN-driven outflows in clumpy media: multiphase structure and scaling relations
  • Jul 26, 2024
  • Monthly Notices of the Royal Astronomical Society
  • S R Ward + 3 more

Small-scale winds driven from accretion discs surrounding active galactic nuclei (AGN) are expected to launch kpc-scale outflows into their host galaxies. However, the ways in which the structure of the interstellar medium (ISM) affects the multiphase content and impact of the outflow remain uncertain. We present a series of numerical experiments featuring a realistic small-scale AGN wind with velocity $5\times 10^3 \!-\! 10^4\rm {\ km\ s^{-1}}$ interacting with an isolated galaxy disc with a manually controlled clumpy ISM, followed at sub-pc resolution. Our simulations are performed with arepo and probe a wide range of AGN luminosities ($L_{\rm {AGN}}{=} 10^{43-47}\rm {\ erg\ s^{-1}}$) and ISM substructures. In homogeneous discs, the AGN wind sweeps up an outflowing, cooling shell, where the emerging cold phase dominates the mass and kinetic energy budgets, reaching a momentum flux $\dot{p} \approx 7\ L/c$. However, when the ISM is clumpy, outflow properties are profoundly different. They contain small, long-lived ($\gtrsim 5\ \rm {Myr}$), cold ($T{\lesssim }10^{4.5}{\rm {\ K}}$) cloudlets entrained in the faster, hot outflow phase, which are only present in the outflow if radiative cooling is included in the simulation. While the cold phase dominates the mass of the outflow, most of the kinetic luminosity is now carried by a tenuous, hot phase with $T \gtrsim 10^7 \, \rm K$. While the hot phases reach momentum fluxes $\dot{p} \approx (1 - 5)\ L/c$, energy-driven bubbles couple to the cold phase inefficiently, producing modest momentum fluxes $\dot{p} \lesssim L/c$ in the fast-outflowing cold gas. These low momentum fluxes could lead to the outflows being misclassified as momentum-driven using common observational diagnostics. We also show predictions for scaling relations between outflow properties and AGN luminosity and discuss the challenges in constraining outflow driving mechanisms and kinetic coupling efficiencies using observed quantities.

  • Research Article
  • 10.1051/0004-6361/202449244
Modelling absorption and emission profiles from accretion disc winds with WINE
  • Nov 1, 2024
  • Astronomy & Astrophysics
  • A Luminari + 4 more

Context. Fast and massive winds are ubiquitously observed in the UV and X-ray spectra of active galactic nuclei (AGNs) and other accretion-powered sources. Several theoretical and observational pieces of evidence suggest they are launched at accretion disc scales, carrying significant mass and angular momentum. Thanks to such high-energy output, they may play an important role in transferring the energy released by accretion to the surrounding environment. In the case of AGNs, this process can help to set the so-called co-evolution between an AGN and its host galaxy, which mutually regulates their growth across cosmic time. To precisely assess the effective role of UV and X-ray winds at accretion disc scales, it is necessary to accurately measure their properties, including mass and energy rates. However, this is a challenging task, due to both the limited signal-to-noise ratio of available observations and the limitations of the models currently used in the spectral analysis. Aims. We aim to maximise the scientific return of current and future observations by improving the theoretical modelling of these winds through our Winds in the Ionised Nuclear Environment (WINE) model. WINE is a spectroscopic model specifically designed for disc winds in AGNs and compact accreting sources, which couples photoionisation and radiative transfer with special relativistic effects and a three-dimensional model of the emission profiles. Methods. We explore with WINE the main spectral features associated with the disc winds in AGNs, with a particular emphasis on the detectability of the wind emission in the total transmitted spectrum. We explore the impact of the wind ionisation, column density, velocity field, and geometry in shaping the emission profiles. We simulated observations with the X-ray microcalorimeter Resolve on board the recently launched XRISM satellite and the X-IFU on board the future Athena mission. This allows us to assess the capabilities of these telescopes in the study of disc winds in X-ray spectra of AGNs for the typical physical properties and exposure times of the sources included in the XRISM performance verification phase. Results. The wind kinematic and geometry (together with the ionisation and column density) deeply affect both shape and strength of the wind spectral features. Thanks to this, both Resolve and, on a longer timescale, X-IFU will be able to accurately constrain the main properties of disc winds over a broad range of ionisation, column densities, and covering factors. We also investigate the impact of the spectral energy distribution (SED) on the resulting appearance of the wind. Our findings reveal a dramatic difference in the gas opacity when using a soft, Narrow Line Seyfert 1-like SED compared to a canonical powerlaw SED with a spectral index of Γ ≈ 2.

  • Research Article
  • Cite Count Icon 131
  • 10.1051/0004-6361/201936606
ALMA images the many faces of the NGC 1068 torus and its surroundings
  • Nov 28, 2019
  • Astronomy & Astrophysics
  • S García-Burillo + 20 more

Aims. We investigate the fueling and the feedback of nuclear activity in the nearby (D = 14 Mpc) Seyfert 2 barred galaxy NGC 1068 by studying the distribution and kinematics of molecular gas in the torus and its connections to the host galaxy disk. Methods. We used the Atacama Large Millimeter Array (ALMA ) to image the emission of a set of molecular gas tracers in the circumnuclear disk (CND) and the torus of the galaxy using the CO(2–1), CO(3–2), and HCO+(4–3) lines and their underlying continuum emission with high spatial resolutions (0.03″ − 0.09″ ≃ 2 − 6 pc). These transitions, which span a wide range of physical conditions of molecular gas (n(H2)⊂103 − 107 cm−3), are instrumental in revealing the density radial stratification and the complex kinematics of the gas in the torus and its surroundings. Results. The ALMA images resolve the CND as an asymmetric ringed disk of D ≃ 400 pc in size and ≃1.4 × 108 M⊙ in mass. The CND shows a marked deficit of molecular gas in its central ≃130 pc region. The inner edge of the ring is associated with the presence of edge-brightened arcs of NIR polarized emission, which are identified with the current working surface of the ionized wind of the active galactic nucleus (AGN). ALMA proves the existence of an elongated molecular disk/torus in NGC 1068 of Mtorusgas ≃ 3 × 105 M⊙, which extends over a large range of spatial scales D ≃ 10 − 30 pc around the central engine. The new observations evidence the density radial stratification of the torus: the HCO+(4–3) torus, with a full size DHCO+(4 − 3) = 11 ± 0.6 pc, is a factor of between two and three smaller than its CO(2–1) and CO(3–2) counterparts, which have full sizes of DCO(3 − 2) = 26 ± 0.6 pc and DCO(2 − 1) = 28 ± 0.6 pc, respectively. This result brings into light the many faces of the molecular torus. The torus is connected to the CND through a network of molecular gas streamers detected inside the CND ring. The kinematics of molecular gas show strong departures from circular motions in the torus, the gas streamers, and the CND ring. These velocity field distortions are interconnected and are part of a 3D outflow that reflects the effects of AGN feedback on the kinematics of molecular gas across a wide range of spatial scales around the central engine. In particular, we estimate through modeling that a significant fraction of the gas inside the torus (≃ 0.4 − 0.6 × Mtorusgas) and a comparable amount of mass along the gas streamers are outflowing. However, the bulk of the mass, momentum, and energy of the molecular outflow of NGC 1068 is contained at larger radii in the CND region, where the AGN wind and the radio jet are currently pushing the gas assembled at the Inner Lindblad Resonance (ILR) ring of the nuclear stellar bar. Conclusions. In our favored scenario a wide-angle AGN wind launched from the accretion disk of NGC1068 is currently impacting a sizable fraction of the gas inside the torus. However, a large gas reservoir (≃1.2 − 1.8 × 105 M⊙), which lies close to the equatorial plane of the torus, remains unaffected by the feedback of the AGN wind and can therefore continue fueling the AGN for at least ≃1 − 4 Myr. Nevertheless, AGN fueling currently seems thwarted on intermediate scales (15 pc ≤r ≤ 50 pc).

  • Research Article
  • Cite Count Icon 9
  • 10.3847/1538-4357/ad004d
The Close AGN Reference Survey (CARS): An Interplay between Radio Jets and AGN Radiation in the Radio-quiet AGN HE0040-1105
  • Dec 1, 2023
  • The Astrophysical Journal
  • M Singha + 16 more

We present a case study of HE 0040-1105, an unobscured radio-quiet active galactic nucleus (AGN) at a high accretion rate of λ Edd = 0.19 ± 0.04. This particular AGN hosts an ionized gas outflow with the largest spatial offset from its nucleus compared to all other AGNs in the Close AGN Reference Survey. By combining multiwavelength observations from the Very Large Telescope/MUSE, Hubble Space Telescope/Wide Field Camera 3, Very Large Array, and European VLBI Network, we probe the ionization conditions, gas kinematics, and radio emission from host galaxy scales to the central few parsecs. We detect four kinematically distinct components, one of which is a spatially unresolved AGN-driven outflow located within the central 500 pc, where it locally dominates the interstellar medium conditions. Its velocity is too low to escape the host galaxy’s gravitational potential, and may be re-accreted onto the central black hole via chaotic cold accretion. We detect compact radio emission in HE 0040-1105 within the region covered by the outflow, varying on a timescale of ∼20 yr. We show that neither AGN coronal emission nor star formation processes wholly explain the radio morphology/spectrum. The spatial alignment between the outflowing ionized gas and the radio continuum emission on 100 pc scales is consistent with a weak jet morphology rather than diffuse radio emission produced by AGN winds. >90% of the outflowing ionized gas emission originates from the central 100 pc, within which the ionizing luminosity of the outflow is comparable to the mechanical power of the radio jet. Although radio jets might primarily drive the outflow in HE 0040-1105, radiation pressure from the AGN may contribute to this process.

  • Research Article
  • Cite Count Icon 3
  • 10.3847/1538-4357/ad2b63
Fast Outflows and Luminous He ii Emission in Dwarf Galaxies with Active Galactic Nuclei (AGN)
  • Apr 1, 2024
  • The Astrophysical Journal
  • Weizhe 伟哲 Liu 刘 + 8 more

While stellar processes are believed to be the main source of feedback in dwarf galaxies, the accumulating discoveries of active galactic nuclei (AGN) in dwarf galaxies over recent years arouse the interest to also consider AGN feedback in them. Fast, AGN-driven outflows, a major mechanism of AGN feedback, have indeed been discovered in dwarf galaxies and may be powerful enough to provide feedback to their dwarf hosts. In this paper, we search for outflows traced by the blueshifted ultraviolet absorption features in three dwarf galaxies with AGN from the sample examined in our previous ground-based study. We confirm outflows traced by blueshifted absorption features in two objects and tentatively detect an outflow in the third object. In one object where the outflow is clearly detected in multiple species, photoionization modeling suggests that this outflow is located ∼0.5 kpc from the AGN, implying a galactic-scale impact. This outflow is much faster and possesses a higher kinetic energy outflow rate than starburst-driven outflows in sources with similar star formation rates, and is likely energetic enough to provide negative feedback to its host galaxy as predicted by simulations. Much broader (∼4000 km s−1) absorption features are also discovered in this object, which may have the same origin as that of broad absorption lines in quasars. Additionally, strong He ii λ1640 emission is detected in both objects where the transition falls in the wavelength coverage and is consistent with an AGN origin. In one of these two objects, a blueshifted He ii λ1640 emission line is clearly detected, likely tracing a highly ionized AGN wind.

  • Research Article
  • Cite Count Icon 8
  • 10.1093/mnras/staa3755
Active galactic nucleus feedback in an elliptical galaxy with the most updated AGN physics: Parameter explorations
  • Dec 5, 2020
  • Monthly Notices of the Royal Astronomical Society
  • Zhiyuan Yao + 2 more

In a previous work, we have proposed a sub-grid model of active galactic nucleus (AGN) feedback by taking into account the state-of-the-art AGN physics, and used that model to study the effect of AGN feedback on the evolution of an isolated elliptical galaxy by performing 2D high-resolution (i.e. the Bondi radius is well resolved) simulations. In that work, typical values of model parameters were adopted. In this work, we extend that study by exploring the effects of uncertainties of parameter values. Such a study is also useful for us to understand the respective roles of various components of the model. These parameters include the mass flux and velocity of AGN wind and radiative efficiency in both the hot and cold feedback modes, and the initial black hole (BH) mass. We find that the velocity of AGN wind in the hot mode is the most important quantity to control the typical accretion rate and luminosity of AGN, and the mass growth of the BH. The effect of the wind on star formation is less sensitive. Within the limited parameter range explored in this work, a stronger AGN wind suppresses star formation within ∼100 pc but enhances star formation beyond this radius, while the star formation integrated over the evolution time and the whole galaxy roughly remain unchanged. AGN radiation suppresses the BH accretion in a mild way, but dust is not considered here. Finally, a smaller initial BH mass results in a more violent evolution of the BH accretion rate. The corresponding AGN spends more time in the high-luminosity state and the percentage of BH mass growth is higher. Our results indicate the robustness of AGN feedback in keeping the galaxy quenched.

  • Research Article
  • Cite Count Icon 42
  • 10.1051/0004-6361/202038256
Multiphase feedback processes in the Sy2 galaxy NGC 5643
  • Dec 22, 2020
  • Astronomy & Astrophysics
  • I García-Bernete + 13 more

We study the multiphase feedback processes in the central ∼3 kpc of the barred Seyfert 2 galaxy NGC 5643. We used observations of the cold molecular gas (ALMA CO(2−1) transition) and ionized gas (MUSE IFU optical emission lines). We studied different regions along the outflow zone, which extends out to ∼2.3 kpc in the same direction (east-west) as the radio jet, as well as nuclear and circumnuclear regions in the host galaxy disk. The CO(2−1) line profiles of regions in the outflow and spiral arms show two or more different velocity components: one associated with the host galaxy rotation, and the others with out- or inflowing material. In the outflow region, the [O III]λ5007 Å emission lines have two or more components: the narrow component traces rotation of the gas in the disk, and the others are related to the ionized outflow. The deprojected outflowing velocities of the cold molecular gas (median Vcentral ∼ 189 km s−1) are generally lower than those of the outflowing ionized gas, which reach deprojected velocities of up to 750 km s−1 close to the active galactic nucleus (AGN), and their spatial profiles follow those of the ionized phase. This suggests that the outflowing molecular gas in the galaxy disk is being entrained by the AGN wind. We derive molecular and ionized outflow masses of ∼5.2 × 107 M⊙ (αCOGalactic) and 8.5 × 104 M⊙ and molecular and ionized outflow mass rates of ∼51 M⊙ yr−1 (αCOGalactic) and 0.14 M⊙ yr−1, respectively. This means that the molecular phase dominates the outflow mass and outflow mass rate, while the kinetic power and momentum of the outflow are similar in both phases. However, the wind momentum loads (Ṗout/ṖAGN) for the molecular and ionized outflow phases are ∼27−5 (αCOGalactic and αCOULIRGs) and < 1, which suggests that the molecular phase is not momentum conserving, but the ionized phase most certainly is. The molecular gas content (Meast ∼ 1.5 × 107 M⊙; αCOGalactic) of the eastern spiral arm is approximately 50−70% of the content of the western one. We interpret this as destruction or clearing of the molecular gas produced by the AGN wind impacting in the eastern side of the host galaxy (negative feedback process). The increase in molecular phase momentum implies that part of the kinetic energy from the AGN wind is transmitted to the molecular outflow. This suggests that in Seyfert-like AGN such as NGC 5643, the radiative or quasar and the kinetic or radio AGN feedback modes coexist and may shape the host galaxies even at kiloparsec scales through both positive and (mild) negative feedback.

More from: The Astrophysical Journal
  • New
  • Research Article
  • 10.3847/1538-4357/ae0a30
Early Stellar Flybys are Unlikely: Improved Constraints from Sednoids and Large-q Trans-Neptunian Objects
  • Nov 7, 2025
  • The Astrophysical Journal
  • Qingru Hu + 3 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae0581
Tidal Disruption Events in Active Galactic Nuclei: on Orbital Inclination and Schwarzschild Apsidal Precession
  • Nov 7, 2025
  • The Astrophysical Journal
  • Minghao Zhang + 4 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae0930
Chemical Abundances of M and G Dwarfs in the Hyades and Coma Berenices Open Clusters from APOGEE Spectra
  • Nov 7, 2025
  • The Astrophysical Journal
  • Deusalete Vilar + 10 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae046d
Mapping Atmospheric Features of the Planetary-mass Brown Dwarf SIMP 0136 with JWST NIRISS
  • Nov 7, 2025
  • The Astrophysical Journal
  • Roman Akhmetshyn + 11 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae0720
A Gigaparsec-scale Hydrodynamic Volume Reconstructed with Deep Learning
  • Nov 7, 2025
  • The Astrophysical Journal
  • Cooper Jacobus + 6 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae09ad
The Periodicity of Three-dimensional Oscillatory Reconnection
  • Nov 7, 2025
  • The Astrophysical Journal
  • Luiz A C A Schiavo + 2 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae0936
pop-cosmos: Insights from Generative Modeling of a Deep, Infrared-selected Galaxy Population
  • Nov 7, 2025
  • The Astrophysical Journal
  • Stephen Thorp + 8 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae10ba
Empirical Optimization of the Source-surface Height in the Potential Field Source Surface Extrapolation
  • Nov 7, 2025
  • The Astrophysical Journal
  • Munehito Shoda + 3 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae070c
Vanishing Refractories: Tracing Dust Evolution in the BP Tau Protoplanetary Disk
  • Nov 6, 2025
  • The Astrophysical Journal
  • Marbely Micolta + 6 more

  • New
  • Research Article
  • 10.3847/1538-4357/ae0a1b
A Mechanism for Electrostatic Solitary Waves Observed in Ganymede’s Magnetopause
  • Nov 6, 2025
  • The Astrophysical Journal
  • R Rubia + 3 more

Save Icon
Up Arrow
Open/Close
  • Ask R Discovery Star icon
  • Chat PDF Star icon

AI summaries and top papers from 250M+ research sources.

Search IconWhat is the difference between bacteria and viruses?
Open In New Tab Icon
Search IconWhat is the function of the immune system?
Open In New Tab Icon
Search IconCan diabetes be passed down from one generation to the next?
Open In New Tab Icon