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Related papers: Starbursts and torus evolution in AGN

200 papers

For most of their lives, galaxies are surrounded by large and massive coronae of hot gas, which constitute vast reservoirs for gas accretion. This Chapter describes a mechanism that allows star-forming disc galaxies to extract gas from…

Astrophysics of Galaxies · Physics 2017-05-31 Filippo Fraternali

The primary source of emission of active galactic nuclei (AGN), the accretion disk, is surrounded by an optically and geometrically thick dusty structure ("the so-called dusty torus"). The infrared radiation emitted by the dust is nothing…

Astrophysics of Galaxies · Physics 2017-01-13 Marko Stalevski , Claudio Ricci , Yoshihiro Ueda , Paulina Lira , Jacopo Fritz , Maarten Baes

Stars are likely embedded in the gas disks of Active Galactic Nuclei (AGN). Theoretical models predict that in the inner regions of the disk these stars accrete rapidly, with fresh gas replenishing hydrogen in their cores faster than it is…

Astrophysics of Galaxies · Physics 2022-04-27 Adam S. Jermyn , Alexander J. Dittmann , B. McKernan , K. E. S. Ford , Matteo Cantiello

The Milky Way Galaxy hosts a four million solar mass black hole, Sgr A*, that underwent a major accretion episode approximately 3-6 Myr ago. During the episode, hundreds of young massive stars formed in a disc orbiting Sgr A* in the central…

Astrophysics of Galaxies · Physics 2022-05-30 A. Generozov , S. Nayakshin , A. M. Madigan

Stellar bars are a common feature in massive disc galaxies. On a theoretical ground, the response of gas to a bar is generally thought to cause nuclear starbursts and, possibly, AGN activity once the perturbed gas reaches the central…

Astrophysics of Galaxies · Physics 2015-10-28 R. Fanali , M. Dotti , D. Fiacconi , F. Haardt

Long-term homogeneous photometry for 35 classical T Tauri stars (cTTS) in the Taurus-Auriga star-forming region (Tau-Aur SFR) has been analyzed. Reliable effective temperatures, interstellar extinctions, luminosities, radii, masses, and…

Solar and Stellar Astrophysics · Physics 2018-07-02 K. N. Grankin

We derive the properties of dusty tori in Active Galactic Nuclei (AGN) from the comparison of observed Spectral Energy Distributions (SEDs) of SDSS quasars and a precomputed grid of torus models. The observed SEDs comprise SDSS photometry,…

The distribution of gravitational torques and bar strengths in the local Universe is derived from a detailed study of 163 galaxies observed in the near-infrared. The results are compared with numerical models for spiral galaxy evolution. It…

Astrophysics · Physics 2009-11-07 David L. Block , Frederic Bournaud , Francoise Combes , Ivanio Puerari , Ron Buta

We present new X-ray and Far Ultraviolet (FUV) observations of T Tauri stars covering the age range 1 to 10 Myr. Our goals are to observationally constrain the intensity of radiation fields responsible for evaporating gas from the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Laura Ingleby , Nuria Calvet , Jesus Hernandez , Cesar Briceno , Catherine Espaillat , Jon Miller , Edwin Bergin , Lee Hartmann

We study outflows driven by Active Galactic Nuclei (AGNs) using high- resolution simulations of idealized z=2 isolated disk galaxies. Episodic accretion events lead to outflows with velocities >1000 km/s and mass outflow rates up to the…

Astrophysics of Galaxies · Physics 2015-06-18 Jared M. Gabor , Frédéric Bournaud

The presence of young stars, aged around several million years and situated within the range of $\sim 0.04-1$ pc from our Galactic center raises a question about their origins and dynamical evolutions. Their kinematics provide an…

Astrophysics of Galaxies · Physics 2024-04-29 Xiao Fan , Qingwen Wu , Jiancheng Wu , Xiangli Lei , Mengye Wang , Fulin Li

Strong iron lines are a common feature of the optical spectra of active galactic nuclei (AGNs) and quasars from $z\sim 6-7$ to the local Universe, and [Fe/Mg] ratios do not show cosmic evolution. During active episodes, accretion disks…

Astrophysics of Galaxies · Physics 2023-11-14 J. -M. Wang , S. , Zhai , Y. -R. Li , Y. -Y. Songsheng , L. C. Ho , Y. -J. Chen , J. -R. Liu , P. Du , Y. -F. Yuan

We use high-resolution ($\simeq$ 35pc) hydrodynamical simulations of galaxy formation to investigate the relation between gas accretion and star formation in galaxies hosted by dark matter haloes of mass $10^{12}$ $\mathrm{M_\odot}$ at $z =…

Astrophysics of Galaxies · Physics 2024-09-24 Zuzanna Kocjan , Corentin Cadiou , Oscar Agertz , Andrew Pontzen

(Abridged) Infrared high-resolution imaging and interferometry have shown that the dust distribution is frequently elongated along the polar direction of an AGN. To explain these findings, we developed a model scenario for the inner ~30 pc…

Astrophysics of Galaxies · Physics 2018-08-15 B. Vollmer , M. Schartmann , L. Burtscher , F. Marin , S. Hoenig , R. Davies , R. Goosmann

We report ALMA observations of CO(3-2) emission in a sample of 7 Seyfert/LINER galaxies at the unprecedented spatial resolution of 0.1'' = 4-9 pc. Our aim is to explore the close environment of AGN, and the dynamical structures leading to…

We analyse star formation in the nuclei of 9 Seyfert galaxies at spatial resolutions down to 0.085arcsec, corresponding to length scales of less than 10pc in some objects. Our data were taken mostly with the near infrared adaptive optics…

Astrophysics · Physics 2009-11-13 R. Davies , F. Mueller Sanchez , R. Genzel , L. Tacconi , E. Hicks , S. Friedrich , A. Sternberg

We present Spitzer 3.6--24 micron photometry and spectroscopy for stars in the 1--3 Myr-old Coronet Cluster, expanding upon the survey of Sicilia-Aguilar et al. (2008). Using sophisticated radiative transfer models, we analyze these new…

Solar and Stellar Astrophysics · Physics 2015-05-27 Thayne Currie , Aurora Sicilia-Aguilar

Stars and planets form in regions of enhanced stellar density, subjecting protoplanetary discs to gravitational perturbations from neighbouring stars. Observations in the Taurus star-forming have uncovered evidence of at least three recent,…

From extensive radiative transfer calculations we find that clumpy torus models with \No \about 5--15 dusty clouds along radial equatorial rays successfully explain AGN infrared observations. The dust has standard Galactic composition, with…

Astrophysics · Physics 2011-02-11 Maia Nenkova , Matthew M. Sirocky , Robert Nikutta , Zeljko Ivezic , Moshe Elitzur

Observations indicate that massive stars form in regions of very high surface density, ~1 g cm^-2. Clusters containing massive stars and globular clusters have a comparable column density. The total pressure in clouds of such a column…

Astrophysics · Physics 2008-11-26 Christopher F. McKee , Jonathan C. Tan