Outflow Bubbles from Compact Binary Mergers Embedded in Active Galactic Nuclei: Cavity Formation and the Impact on Electromagnetic Counterparts

AbstractMulti-phase filamentary structures surrounding giant elliptical galaxies at the center of cool-core clusters, the Brightest Cluster Galaxies (BCGs), have been detected from optical to submillimeter wavelengths. The source of the ionisation in the filaments is still debated. Studying the excitation of these structures is key to our understanding of Active Galactic Nuclei (AGN) feedback in general, and more precisely of the impact of environmental and local effects on star formation. One possible contributor to the excitation of the filaments is the thermal radiation from the cooling of the hot plasma surrounding the BCGs, the so-called cooling flow.

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Numerical Simulations of Jets from Active Galactic Nuclei

Galaxies ◽

10.3390/galaxies7010024 ◽

2019 ◽

Vol 7 (1) ◽

pp. 24 ◽

Cited By ~ 6

Author(s):

José-María Martí

Keyword(s):

Numerical Simulations ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Theoretical Models ◽

The Status ◽

Hydrodynamical Description ◽

Jet Plasma ◽

The Impact ◽

Continuous Injection ◽

Double Radio Galaxies

Numerical simulations have been playing a crucial role in the understanding of jets from active galactic nuclei (AGN) since the advent of the first theoretical models for the inflation of giant double radio galaxies by continuous injection in the late 1970s. In the almost four decades of numerical jet research, the complexity and physical detail of simulations, based mainly on a hydrodynamical/magneto-hydrodynamical description of the jet plasma, have been increasing with the pace of the advance in theoretical models, computational tools and numerical methods. The present review summarizes the status of the numerical simulations of jets from AGNs, from the formation region in the neighborhood of the supermassive central black hole up to the impact point well beyond the galactic scales. Special attention is paid to discuss the achievements of present simulations in interpreting the phenomenology of jets as well as their current limitations and challenges.

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Hydrodynamic simulations of AGN jets: the impact of Riemann solvers and spatial reconstruction schemes on jet evolution

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2657 ◽

2020 ◽

Vol 498 (3) ◽

pp. 3870-3887

Author(s):

G Musoke ◽

A J Young ◽

M Birkinshaw

Keyword(s):

Active Galactic Nuclei ◽

Numerical Algorithms ◽

Galactic Nuclei ◽

Riemann Solver ◽

Third Order ◽

Riemann Solvers ◽

Hydrodynamic Simulations ◽

Spatial Reconstruction ◽

High Level ◽

The Impact

ABSTRACT Numerical simulations play an essential role in helping us to understand the physical processes behind relativistic jets in active galactic nuclei. The large number of hydrodynamic codes available today enables a variety of different numerical algorithms to be utilized when conducting the simulations. Since many of the simulations presented in the literature use different combinations of algorithms it is important to quantify the differences in jet evolution that can arise due to the precise numerical schemes used. We conduct a series of simulations using the flash (magneto-)hydrodynamics code in which we vary the Riemann solver and spatial reconstruction schemes to determine their impact on the evolution and dynamics of the jets. For highly refined grids the variation in the simulation results introduced by the different combinations of spatial reconstruction scheme and Riemann solver is typically small. A high level of convergence is found for simulations using third-order spatial reconstruction with the Harten–Lax–Van-Leer with contact and Hybrid Riemann solvers.

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Density diagnostics of photoionized outflows in active galactic nuclei

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319007750 ◽

2019 ◽

Vol 15 (S350) ◽

pp. 274-277

Author(s):

Junjie Mao

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

State Of The Art ◽

Density Measurement ◽

Galactic Nuclei ◽

Next Generation ◽

Host Galaxies ◽

Current Generation ◽

X Ray ◽

The Impact

AbstractPhotoionized outflows in active galactic nuclei (AGNs) are thought to influence their circumnuclear and host galactic environment. However, the distance of the outflow with respect to the black hole is poorly constrained, which limits our understanding of the kinetic power by the outflow. Therefore, the impact of AGN outflows on their host galaxies is uncertain. If the density of the outflow is known, its distance can be derived. Density measurement via variability studies and density sensitive lines have been used, albeit not very effective in the X-ray band. Good measurements are rather demanding or challenging for the current generation of (grating) spectrometers. The next generation of spectrometers will certainly provide data with better quality and large quantity, leading to tight constraints on the location and the kinetic power of AGN outflows. This contribution summarizes the state-of-the-art in this field.

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The impact of disturbed galaxy clusters on the kinematics of active galactic nuclei

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3154 ◽

2020 ◽

Vol 499 (3) ◽

pp. 3792-3805

Author(s):

Lawrence E Bilton ◽

Kevin A Pimbblet ◽

Yjan A Gordon

Keyword(s):

Active Galactic Nuclei ◽

Galaxy Clusters ◽

Velocity Dispersion ◽

Signal To Noise Ratio ◽

Galactic Nuclei ◽

Sloan Digital Sky Survey ◽

X Ray ◽

Cluster Galaxies ◽

Sky Survey ◽

The Impact

ABSTRACT We produce a kinematic analysis of AGN-hosting cluster galaxies from a sample of 33 galaxy clusters selected using the X-ray Clusters Database (BAX) and populated with galaxies from the Sloan Digital Sky Survey Data Release 8. The 33 galaxy clusters are delimited by their relative intensity of member galaxy substructuring as a proxy to core merging to derive two smaller sub-samples of 8 dynamically active (merging) and 25 dynamically relaxed (non-merging) states. The AGN were selected for each cluster sub-sample by employing the WHAN diagram to the strict criteria of log10([N ii]/Hα) ≥ −0.32 and EWHα ≥ 6 Å, providing pools of 70 mergings and 225 non-merging AGN sub-populations. By co-adding the clusters to their respective dynamical states to improve the signal-to-noise ratio of our AGN sub-populations we find that merging galaxy clusters on average host kinematically active AGN between 0–1.5r200 as r200 → 0, where their velocity dispersion profile (VDP) presents a significant deviation from the non-AGN sub-population VDP by ≳3σ. This result is indicative that the AGN-hosting cluster galaxies have recently coalesced on to a common potential. Further analysis of the composite distributions illustrates non-merging AGN-hosting sub-populations have, on average, already been accreted and predominantly lie within backsplash regions of the projected phase-space. This suggests merging cluster dynamical states hold relatively younger AGN sub-populations kinematically compared with those found in non-merging cluster dynamical states.

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Astrotomography

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312000646 ◽

2011 ◽

Vol 7 (S285) ◽

pp. 227-234

Author(s):

Keith Horne ◽

Raymundo Baptista ◽

Misty C. Bentz ◽

Danny Steeghs

Keyword(s):

Active Galactic Nuclei ◽

Imaging Techniques ◽

Binary Star ◽

Galactic Nuclei ◽

Rotating Stars ◽

Time Resolved ◽

Accretion Flows ◽

Compact Binary ◽

Doppler Shifts ◽

Rapidly Rotating Stars

AbstractAstrotomography refers to a suite of indirect imaging techniques that achieve micro-arcsecond angular resolution by measuring projections obtained from time-resolved spectroscopic observations. The projections arise from Doppler shifts, eclipses or time delays, combined with rotation of the star or binary system being imaged. At our workshop we reviewed and discussed state-of-the-art methods for imaging the surfaces and magnetic fields of rapidly rotating stars, the accretion flows in compact binary star systems and the broad emission-line regions in active galactic nuclei.

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THE IMPACT OF INTERACTIONS, BARS, BULGES, AND ACTIVE GALACTIC NUCLEI ON STAR FORMATION EFFICIENCY IN LOCAL MASSIVE GALAXIES

The Astrophysical Journal ◽

10.1088/0004-637x/758/2/73 ◽

2012 ◽

Vol 758 (2) ◽

pp. 73 ◽

Cited By ~ 165

Author(s):

Amélie Saintonge ◽

Linda J. Tacconi ◽

Silvia Fabello ◽

Jing Wang ◽

Barbara Catinella ◽

...

Keyword(s):

Star Formation ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Massive Galaxies ◽

Formation Efficiency ◽

The Impact

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Gamma-ray Bursts Progress and Problems

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317001788 ◽

2016 ◽

Vol 12 (S324) ◽

pp. 49-53

Author(s):

N. R. Tanvir

Keyword(s):

Galaxy Evolution ◽

Gamma Ray ◽

Gamma Ray Bursts ◽

Compact Binary ◽

Distant Galaxies ◽

Long Duration ◽

Massive Neutron Star ◽

Binary Mergers ◽

The Impact ◽

The Universe

AbstractOur understanding of gamma-ray bursts (GRBs) has come a long way in the past fifty years since their first detection. We now know that GRBs arise in distant galaxies and that there are at least two distinct sub-classes, the long-duration class being produced by some rare massive star core collapse and the short-duration class likely by compact binary mergers involved neutron stars. In both cases, the final remnant will be a stellar-mass black-hole or a massive neutron star. The bursts themselves are associated with ultra-relativistic jetted outflows created by these events, and their afterglows by the impact of these outflows on the surrounding circumburst material. Increasingly GRBs are also being used as probes of the universe, both for understanding galaxy evolution back to the era of reionization, and for the physics of gravitational wave sources. However, many aspects of GRBs remain poorly understood, some pointers to which are given here.

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Feeding and feedback in nuclei of galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320002239 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 307-311

Author(s):

Anelise Audibert ◽

Françoise Combes ◽

Santiago García-Burillo ◽

Kalliopi Dasyra

Keyword(s):

High Resolution ◽

Active Galactic Nuclei ◽

Galaxy Evolution ◽

Galactic Nuclei ◽

Radio Galaxies ◽

Host Galaxy ◽

Molecular Gas ◽

Molecular Outflows ◽

Radio Jets ◽

The Impact

AbstractOur aim is to explore the close environment of Active Galactic Nuclei (AGN) and its connection to the host galaxy through the morphology and dynamics of the cold gas inside the central kpc in nearby AGN. We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of AGN feeding and feedback caught in action in NGC613 and NGC1808 at high resolution (few pc), part of the NUclei of GAlaxies (NUGA) project. We detected trailing spirals inside the central 100 pc, efficiently driving the molecular gas into the SMBH, and molecular outflows driven by the AGN. We present preliminary results of the impact of massive winds induced by radio jets on galaxy evolution, based on observations of radio galaxies from the ALMA Radio-source Catalogue.

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