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Related papers: Active galactic nuclei and massive galaxy cores

200 papers

We consider the emission of high energy to very high energy $\gamma$-rays in radio-quiet active galactic nuclei (AGN) or the central regions of radio-loud AGN. We use our results to estimate the $\gamma$-ray flux from the central regions of…

Astrophysics · Physics 2011-05-12 P. A. Johnson , A. Mastichiadis , R. J. Protheroe , T. S. Stanev , A. P. Szabo

A supermassive black hole has been found at the centre of nearly every galaxy observed with sufficient sensitivity. The masses of these black holes are observed to increase with either the total mass or the mean (random) velocity of the…

Feedback by active galactic nuclei (AGN) is frequently invoked to explain the cut-off of the galaxy luminosity function at the bright end and the absence of cooling flows in galaxy clusters. Meanwhile, there are recent observations of shock…

Astrophysics · Physics 2009-11-13 M. Brueggen , S. Heinz , E. Roediger , M. Ruszkowski , A. Simionescu

The subject of the paper is the role of the massive stellar cluster in the activity phenomenon and in the structure of active galactic nuclei. We introduce a simple model of stellar dynamics in the internal part of the cluster, which allows…

Astrophysics · Physics 2009-11-07 E. Y. Vilkoviskij , B. Czerny

Active galactic nuclei (AGNs) are occasionally seen in pairs, suggesting that tidal encounters are responsible for the accretion of material by both central supermassive black holes (BHs). In Paper I of this series, we selected a sample of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Xin Liu , Yue Shen , Michael A. Strauss

Active galactic nuclei (AGN) play a crucial role in galaxy evolution by influencing the observational properties of their host galaxies. We investigate the host galaxy properties of X-ray selected AGNs, focusing on differences between…

Astrophysics of Galaxies · Physics 2025-08-28 Carlos G. Bornancini , Gabriel A. Oio , Georgina Coldwell

Active Galactic Nuclei (AGN) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight, yet the specific inclinations of all but a few AGN are generally…

Astrophysics of Galaxies · Physics 2015-06-18 T. C. Fischer , D. M. Crenshaw , S. B. Kraemer , H. R. Schmitt , T. J. Turner

The active galactic nucleus (AGN) phenomena results from a supermassive black hole accreting its surrounding gaseous and dusty material. The infrared (IR) regime provides most of the information to characterize the dusty structures that…

Astrophysics of Galaxies · Physics 2022-05-31 Jianwei Lyu , George Rieke

We perform a quantitative morphological comparison between the hosts of Active Galactic Nuclei (AGN) and quiescent galaxies at intermediate redshifts (z~0.7). The imaging data are taken from the large HST/ACS mosaics of the GEMS and STAGES…

To investigate the effect of feedback from active galactic nuclei (AGN) on their surrounding medium, we study the diffuse X-ray emission from galaxy groups and clusters by coupling the Astrophysical Plasma Emission Code (APEC) with the…

[Abridged] We present an analysis of optical spectroscopically-identified AGN to M*+1 in a sample of 6 self-similar SDSS galaxy clusters at z=0.07. These clusters are specifically selected to lack significant substructure at bright limits…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 K. A. Pimbblet , S. S. Shabala , C. P. Haines , A. Fraser-McKelvie , D. J. E. Floyd

The majority of massive black holes (MBHs) likely hosted gas discs during their lifetimes. These could either be long-lived active galactic nuclei (AGN) discs, or shorter-lived discs formed following singular gas infall events, as was…

Astrophysics of Galaxies · Physics 2024-04-12 Aleksey Generozov , Hagai B. Perets

Central starbursts and Active Galactic Nuclei (AGN) are thought to be fueled by either galaxy interactions or secular processes in gravitationally unstable discs. We employ cosmological hydrodynamic simulations from the Feedback in…

We use cosmological hydrodynamical simulations to investigate the role of feedback from accreting black holes on the evolution of sizes, compactness, stellar core density and specific star-formation of massive galaxies with stellar masses…

Astrophysics of Galaxies · Physics 2018-10-24 Ena Choi , Rachel S. Somerville , Jeremiah P. Ostriker , Thorsten Naab , Michaela Hirschmann

Star formation in the universe's largest galaxies---the ones at the centers of galaxy clusters---depends critically on the thermodynamic state of their hot gaseous atmospheres. Central galaxies with low-entropy, high-density atmospheres…

Astrophysics of Galaxies · Physics 2015-06-22 G. M. Voit , M. Donahue

Galactic bars are often suspected to be a channel of gas inflow to the galactic center and trigger central star formation and active galactic nuclei (AGN) activity. However, the current status on this issue based on empirical studies is…

Astrophysics of Galaxies · Physics 2015-06-03 Seulhee Oh , Kyuseok Oh , Sukyoung K. Yi

The presence of absorbing gas around the central engine of Active Galactic Nuclei (AGN) is a common feature of these objects. Recent work has looked at the effect of the dust component of the gas, and how it enhances radiation pressure such…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 S. I. Raimundo , A. C. Fabian , F. E. Bauer , D. M. Alexander , W. N. Brandt , B. Luo , R. V. Vasudevan , Y. Q. Xue

Disks of gas accreting onto supermassive black holes are thought to power active galactic nuclei (AGN). Stars may form in gravitationally unstable regions of these disks, or may be captured from nuclear star clusters. Because of the dense…

Astrophysics of Galaxies · Physics 2021-08-04 Alexander J. Dittmann , Matteo Cantiello , Adam S. Jermyn

We present gas temperature, density, entropy and cooling time profiles for the cores of a sample of 15 galaxy groups observed with {\it Chandra}. We find that the entropy profiles follow a power-law profile down to very small fractions of…

Astrophysics · Physics 2007-05-23 N. N. Jetha , T. J. Ponman , M. J. Hardcastle , J. Croston

We present spectroscopic evidence for a low-luminosity, low-excitation active galactic nucleus (AGN) in NGC 1042, powered by an intermediate-mass black hole. These findings are significant in that the AGN is coincident with a compact star…