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We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull AGNs in the COSMOS field. These objects exhibit the X-ray luminosity of an active galactic nucleus (AGN) but lack broad and narrow emission lines in their…

In this paper we consider the process of alignment of a spinning black hole and a surrounding misaligned accretion disc. We use a simplified set of equations, that describe the evolution of the system in the case where the propagation of…

Astrophysics · Physics 2009-11-11 G. Lodato , J. E. Pringle

Most of the action in Active Galactic Nuclei (AGN) occurs within a few tens of gravitational radii from the supermassive black hole, where matter in the accretion disk may lose up to almost half of its energy with a copious production of…

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

Massive molecular gas has been discovered in giant elliptical galaxies at the centers of galaxy clusters. To reveal its role in active galactic nucleus (AGN) feedback in those galaxies, we construct a semianalytical model of gas…

Astrophysics of Galaxies · Physics 2022-01-10 Yutaka Fujita , Nozomu Kawakatu , Hiroshi Nagai

Active galactic nuclei (AGN) are supermassive black holes with luminous accretion disks found in some galaxies, and are thought to play an important role in galaxy evolution. However, traditional optical spectroscopy for identifying AGN…

Astrophysics of Galaxies · Physics 2022-12-16 Ziting Guo , John F. Wu , Chelsea E. Sharon

Changing-look active galactic nuclei (CL-AGNs) challenges the standard accretion theory owing to its rapid variability. Recent numerical simulations have shown that, for the sub-Eddington accretion case, the disk is magnetic…

High Energy Astrophysical Phenomena · Physics 2023-09-11 Wen-Biao Wu , Wei-Min Gu

Disk continuum reverberation mapping is one of the primary ways we learn about active galactic nuclei (AGN) accretion disks. Reverberation mapping assumes that time-varying X-rays incident on the accretion disk drive variability in…

High Energy Astrophysical Phenomena · Physics 2025-01-14 Amy Secunda , Yan-Fei Jiang , Jenny E. Greene

Surprisingly, the relict cosmological constant has a crucial influence on properties of accretion discs orbiting black holes in quasars and active galactic nuclei. We show it by considering basic properties of both the geometrically thin…

Astrophysics · Physics 2009-11-13 Z. Stuchlik

We present spatially resolved kinematic measurements of stellar and ionized gas components of dwarf galaxies in the stellar mass range $10^{8.5} - 10^{10} M_{\odot}$, selected from SDSS DR7 and DR8 and followed-up with Keck/LRIS…

Astrophysics of Galaxies · Physics 2020-09-04 Christina M Manzano-King , Gabriela Canalizo

The energy released by Active Galactic Nuclei (AGN) in the form of radiation, winds, or radio plasma jets, is known to impact on the surrounding interstellar medium. The result of these processes, known as AGN (negative) feedback, is…

Astrophysics of Galaxies · Physics 2017-12-15 Raffaella Morganti

Context. Warm corona is a possible explanation for Soft X-ray Excess in Active Galactic Nuclei (AGN). This paper contains self consistent modeling of both: accretion disk with optically thick corona, where the gas is heated by…

High Energy Astrophysical Phenomena · Physics 2023-07-26 Dominik Gronkiewicz , Agata Różańska , Pierre-Olivier Petrucci , Renaud Belmont

The outer regions of AGN disks have temperatures similar to those of circumstellar disks, permitting dust condensation. Therefore, planet formation and growth could be active in these dust tori through similar mechanisms. We aim at…

Earth and Planetary Astrophysics · Physics 2026-05-20 Bhupendra Mishra , Wladimir Lyra , Barry McKernan , Mordecai-Mark Mac Low , K. E. Saavik Ford , Harrison E. Cook

We propose that the accretion disks fueling active galactic nuclei are supported vertically against gravity by a strong toroidal ($\phi-$direction) magnetic field that develops naturally as the result of an accretion disk dynamo. The…

High Energy Astrophysical Phenomena · Physics 2016-10-12 Mitchell C. Begelman , Joseph Silk

We explore the properties of cold gravitoturbulent accretion disks - non-fragmenting disks hovering on the verge of gravitational instability - using a realistic prescription for the effective viscosity caused by gravitational torques. This…

Earth and Planetary Astrophysics · Physics 2009-10-02 Roman R. Rafikov

Active Galactic Nuclei (AGN) represent the growth phases of the supermassive black holes in the center of almost every galaxy. Powerful, highly ionized winds, with velocities $\sim 0.1- 0.2c$ are a common feature in X--ray spectra of…

Astrophysics of Galaxies · Physics 2015-09-23 Andrew King , Ken Pounds

The observable characteristics of gamma-ray bursts (GRBs) embedded in the accretion disk of active galactic nuclei (AGNs) are mainly determined by the jet propagation within the disk. In the massive collapsar scenario, we consider that the…

High Energy Astrophysical Phenomena · Physics 2025-11-20 Yun-Feng Wei , Tong Liu , Bao-Quan Huang

Establishing the role of active galactic nuclei (AGN) during the formation of galaxies remains one of the greatest challenges of galaxy formation theory. Towards addressing this, we summarise our recent work investigating: (1) the physical…

Astrophysics of Galaxies · Physics 2021-07-01 C. M. Harrison , S. J. Molyneux , J. Scholtz , M. E. Jarvis

Massive stars can form within or be captured by AGN disks, influencing both the thermal structure and metallicity of the disk environment. In a previous work, we investigated isotropic accretion onto massive stars from a gas-rich,…

High Energy Astrophysical Phenomena · Physics 2025-05-21 Yi-Xian Chen , Yan-Fei Jiang , Jeremy Goodman

The luminous electromagnetic emission from distant active galactic nuclei (AGNs) including quasars is believed to be powered by accretion onto super-massive black holes (SMBHs). In the standard unification model for AGNs a dusty torus…

Astrophysics · Physics 2009-11-10 Shuang Nan Zhang