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Related papers: Active galactic nuclei at z ~ 1.5: I. Spectral ene…

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This is the third paper in a series describing the spectroscopic properties of a sample of 39 AGN at $z \sim 1.5$, selected to cover a large range in black hole mass ($M_{BH}$) and Eddington ratio ($L/L_{Edd}$). In this paper, we continue…

Astrophysics of Galaxies · Physics 2016-04-27 Daniel M. Capellupo , Hagai Netzer , Paulina Lira , Benny Trakhtenbrot , Julián Mejía-Restrepo

Modeling the spectral energy distribution (SED) of active galactic nuclei (AGN) plays a very important role in constraining modern cosmological simulations of galaxy formation. Here, we utilize an advanced supermassive black hole (SMBH)…

Astrophysics of Galaxies · Physics 2026-03-23 Tong Su , Qi Guo , Erlin Qiao , Wenxiang Pei , Luis C. Ho , Cedric G. Lacey

The radiative efficiencies ($\eta$) of 72 luminous unobscured Active Galactic Nuclei (AGNs) at $z\sim1.5-3.5$, powered by some of the most massive black holes (BHs), are constrained. The analysis is based on accretion disk (AD) models,…

Astrophysics of Galaxies · Physics 2014-06-18 Benny Trakhtenbrot

We present the results from performing spectral energy distribution (SED) fitting on 121 variable active galactic nuclei (AGN) candidates in the Hubble Ultra Deep Field (HUDF) using photometry from both the Hubble Space Telescope (HST) and…

We continue our study of the spectral energy distributions (SEDs) of 11 AGN at 1.5 < z < 2.2, with optical-NIR spectra, X-ray data and mid-IR photometry. In a previous paper we presented the observations and models; in this paper we explore…

High Energy Astrophysical Phenomena · Physics 2016-12-14 James S. Collinson , Martin J. Ward , Hermine Landt , Chris Done , Martin Elvis , Jonathan C. McDowell

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

Active galactic nuclei (AGN) are powered by the accretion of disks of gas onto supermassive black holes (SMBHs). Stars and stellar remnants orbiting the SMBH in the nuclear star cluster (NSC) will interact with the AGN disk. Orbiters…

Astrophysics of Galaxies · Physics 2020-11-02 Gaia Fabj , Syeda S. Nasim , Freddy Caban , K. E. Saavik Ford , Barry McKernan , Jillian M. Bellovary

Spectral Energy Distribution (SED) of the broad-band continuum emission from black-hole accretion discs can serve as a tool to measure parameters of the central body and constrain the geometry of the inner accretion flow. We focus on the…

High Energy Astrophysical Phenomena · Physics 2023-06-21 Marcel Štolc , Michal Zajaček , Bożena Czerny , Vladimír Karas

Several properties of the standard alpha-disc model for active galactic nuclei (AGN) are not entirely consistent with AGN observations. As well as such discrepencies, observations show evidence for the existence of high mass outflow winds…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Oren Slone , Hagai Netzer

A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the underlying accretion physics. We present wide frequency…

Active galactic nuclei (AGN) are powered by accretion disks onto supermassive black holes in the the centers of galaxies. AGN are believed to play important roles in the evolution of both supermassive black holes and their host galaxies…

High Energy Astrophysical Phenomena · Physics 2025-06-11 K. E. Saavik Ford , Barry McKernan

The co-evolution of host galaxies and the active black holes which reside in their centre is one of the most important topics in modern observational cosmology. Here we present a study of the properties of obscured Active Galactic Nuclei…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Brusa , F. Fiore , P. Santini , A. Grazian , A. Comastri , G. Zamorani , G. Hasinger , A. Merloni , F. Civano , A. Fontana , V. Mainieri

There is strong observational evidence that many active galactic nuclei (AGNs) harbour supermassive black holes (SMBHs), demonstrating multi-accretion episodes during their lifetime. In such AGNs, corotating and counterrotating tori, or…

High Energy Astrophysical Phenomena · Physics 2018-10-23 D. Pugliese , Z. Stuchlik

The spectra of Active Galactic Nuclei (AGNs) are often characterized by a wealth of emission lines with different profiles and intensity ratios that led to a complicated classification. Their electro-magnetic radiation spans more than 10…

We present ongoing work on the spectral energy distributions (SEDs) of active galactic nuclei (AGNs), derived from X-ray, ultraviolet, optical, infrared and radio photometry and spectroscopy. Our work is motivated by new wide-field imaging…

Astrophysics of Galaxies · Physics 2020-06-17 M. J. I. Brown , K. J. Duncan , H. Landt , M. Kirk , C. Ricci , N. Kamraj

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

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

Apart from viewing-dependent obscuration, intrinsic broad-line emission from active galactic nuclei (AGNs) follows an evolutionary sequence: Type $1 \to 1.2/1.5 \to 1.8/1.9 \to 2$ as the accretion rate onto the central black hole is…

Astrophysics of Galaxies · Physics 2015-06-18 Moshe Elitzur , Luis C. Ho , Jonathan R. Trump

Spectral energy distributions (SEDs) of the central few tens of parsec region of some of the nearest, most well studied, active galactic nuclei (AGN) are presented. These genuine AGN-core SEDs, mostly from Seyfert galaxies, are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. A. Prieto , J. Reunanen , K. R. W. Tristram , N. Neumayer , J. A. Fernandez-Ontiveros , M. Orienti , K. Meisenheimer

The vast amount of energy released by active galactic nuclei (AGN) is increasingly recognized as a key driver of evolution not only in massive galaxies and clusters, but also in low-mass dwarf galaxies. Despite this, their role in the early…

Astrophysics of Galaxies · Physics 2025-07-04 Mahsa Sanati , Julien Devriendt , SergioMartin-Alvarez , Adrianne Slyz , Jonathan C. Tan
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