English
Related papers

Related papers: A Single Intrinsic Luminosity Function for Both Ty…

200 papers

The inevitable spread in properties of the toroidal obscuration of active galactic nuclei (AGNs) invalidates the widespread notion that type 1 and 2 AGNs are intrinsically the same objects, drawn randomly from the distribution of torus…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Moshe Elitzur

We describe improved modelling of the emission by dust in a toroidal--like structure heated by a central illuminating source within Active Galactic Nuclei (AGN). We chose a simple but realistic torus geometry, a flared disc, and a dust…

Astrophysics · Physics 2009-11-13 J. Fritz , A. Franceschini , E. Hatziminaoglou

This review describes recent developments related to the unified model of active galactic nuclei (AGN). It focuses on new ideas about the origin and properties of the central obscurer (torus), and the connection with its surrounding. The…

Astrophysics of Galaxies · Physics 2015-09-23 Hagai Netzer

Active galactic nuclei (AGN) are generally accepted to be powered by the release of gravitational energy in a compact accretion disk surrounding a massive black hole. Such disks are also necessary to collimate powerful radio jets seen in…

Astrophysics · Physics 2009-10-30 Jack F. Gallimore , Stefi A. Baum , Christopher P. O'Dea

Observations give strong support for the unification scheme of active galactic nuclei. Clumpiness of the toroidal obscuration is crucial for explaining the IR observations and has significance consequences for AGN classification: type 1 and…

Astrophysics · Physics 2007-05-23 Moshe Elitzur

Active Galactic Nuclei (AGN) are extremely powerful cosmic objects, driven by accretion of hot gas upon super-massive black holes. The zoo of AGN classes are divided into two major groups, with Type-1 AGN displaying broad Balmer emission…

Active Galactic Nuclei (AGN) are powered by the accretion of material onto a supermassive black hole (SMBH), and are among the most luminous objects in the Universe. However, the huge radiative power of most AGN cannot be seen directly, as…

Astrophysics of Galaxies · Physics 2018-10-17 Ryan C. Hickox , David M. Alexander

An integral part of the Unified Model for Active Galactic Nuclei (AGNs) is an axisymmetric obscuring medium, which is commonly depicted as a torus of gas and dust surrounding the central engine. However, a robust, dynamical model of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. K. Keating , J. E. Everett , S. C. Gallagher , R. P. Deo

The advent of high-angular resolution IR and sub-mm interferometry allows for spatially-resolved observations of the parsec-scale environment of active galactic nuclei (AGN), commonly referred to as the "torus." While molecular lines show…

Astrophysics of Galaxies · Physics 2019-11-06 Sebastian F. Hönig

We have newly identified a substantial number of type 1 active galactic nuclei (AGN) featuring weak broad-line regions (BLRs) at z < 0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects…

Astrophysics of Galaxies · Physics 2015-07-15 Kyuseok Oh , Sukyoung K. Yi , Kevin Schawinski , Michael Koss , Benny Trakhtenbrot

Active Galactic Nuclei (AGN) are highly energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, which present unique observational signatures covering the full electromagnetic spectrum (and more) over…

High Energy Astrophysical Phenomena · Physics 2023-04-05 Stefano Bianchi , Vincenzo Mainieri , Paolo Padovani

Type 2 active galactic nuclei (AGN) show signatures of accretion onto a supermassive black hole through strong, high-ionization, narrow emission lines extended on scales of 100s to 1000s of parsecs, but they lack the broad emission lines…

High Energy Astrophysical Phenomena · Physics 2022-09-21 M. Lynne Saade , Murray Brightman , Daniel Stern , Matthew A. Malkan , Javier A. Garcia

The emission line luminosity function of active galactic nuclei (AGN) is measured from about 3000 AGN included in the main galaxy sample of the Sloan Digital Sky Survey within a redshift range of $0<z<0.15$. The $\Ha$ and [OIII]$\lambda…

The motivation of the "unified model" is to explain the main properties of the large zoo of active galactic nuclei with a single physical object. The discovery of broad permitted lines in the polarized spectrum of type 2 Seyfert galaxies in…

Astrophysics of Galaxies · Physics 2021-02-03 Luigi Spinoglio , Juan Antonio Fernández-Ontiveros

Active Galactic Nuclei (AGN) unification, which implies a large number of obscured AGN, can explain the optical, infrared and X-ray content of deep multiwavelength surveys. Here, we show that the same model also successfully explains the…

Astrophysics · Physics 2007-05-23 Ezequiel Treister , C. M. Urry

The merger of two or more galaxies can enhance the inflow of material from galactic scales into the close environments of Active Galactic Nuclei (AGN), obscuring and feeding the supermassive black hole (SMBH). Both recent simulations and…

We investigated the gas obscuration and host galaxy properties of active galactic nuclei (AGN) during the peak of cosmic accretion growth of supermassive black holes (SMBHs) at redshift 0.8-1.8 using X-ray detected AGN with mid-infrared and…

The orientation-based unification model of active galactic nuclei (AGNs) posits that the principle difference between obscured (Type 2) and unobscured (Type 1) AGNs is the line-of-sight into the central engine. If this model is correct than…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 D. R. Ballantyne

The unified model of active galactic nuclei (AGNs) proposes that different AGN optical spectral types are caused by different viewing angles with respect to an obscuring 'torus'. Therefore, this model predicts that type 1 and type 2 AGNs…

Astrophysics of Galaxies · Physics 2019-06-12 Fan Zou , Guang Yang , William N. Brandt , Yongquan Xue

We present a study of the connection between black hole accretion, star formation, and galaxy morphology at z<=2.5. We focus on active galactic nuclei (AGNs) selected by their mid-IR power-law emission. By fitting optical to far-IR…

‹ Prev 1 2 3 10 Next ›