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Related papers: Multiple Emission States in Active Galactic Nuclei

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We analysed 385 galactic spectra from the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) that belong to the catalog of isolated pairs of galaxies by Karachentsev. The spectra corresponds to physical pairs of galaxies as defined by V…

The impact of feedback from Active Galactic Nuclei (AGN) on the cosmological evolution of the large scale structure is a long studied problem. However, it is still not well understood how the feedback energy couples to the ambient medium to…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-20 Rudrani Kar Chowdhury , Suchetana Chatterjee , Ankit Paul , Craig L. Sarazin , Jane Lixin Dai

We use the Athena hydrodynamics code to model propagating two-dimensional relativistic jets as approximations to the growth of radio-loud active galactic nuclei for various input jet velocities and jet-to-ambient matter density ratios.…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Maxwell Pollack , David Pauls , Paul J. Wiita

We discuss the impact of special relativistic effects on the observed light curves and variability duty cycles of AGNs. We model the properties of AGN light curves at radio wavelengths using a simulated shot noise process in which the…

Astrophysics · Physics 2009-11-07 Matthew L. Lister

We have used the STOKES radiative transfer code, to model polarization induced by dust scattering in the polar regions of Active Galactic Nuclei (AGN). We discuss the wavelength-dependence of the spectral intensity and polarization over the…

Astrophysics · Physics 2007-05-23 Rene W. Goosmann , C. Martin Gaskell , M. Shoji

Non-blazar Active Galactic Nuclei (AGN) have emerged as a new gamma-ray emitting source class on the extragalactic sky and started to deepen our understanding of the physical processes and the nature of AGN in general. The detection of…

High Energy Astrophysical Phenomena · Physics 2017-07-10 Frank M. Rieger

We perform a census of ionized gas outflows using a sample of ~23,000 type 2 active galactic nuclei (AGNs) out to z~0.1. By measuring the velocity offset of narrow emission lines, i.e., [O III] {\lambda}5007 and H{\alpha}, with respect to…

Astrophysics of Galaxies · Physics 2014-10-14 Hyun-Jin Bae , Jong-Hak Woo

We analysed the centre of NGC 1566, which hosts a well-studied active galactic nucleus (AGN), known for its variability. With the aid of techniques such as Principal Component Analysis Tomography, analysis of the emission-line spectra,…

Astrophysics of Galaxies · Physics 2017-07-11 Patrícia da Silva , J. E. Steiner , R. B. Menezes

Merger-remnant galaxies with kpc-scale separation dual active galactic nuclei (AGNs) should be widespread as a consequence of galaxy mergers and triggered gas accretion onto supermassive black holes, yet very few dual AGNs have been…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-19 Julia M. Comerford , Brian F. Gerke , Daniel Stern , Michael C. Cooper , Benjamin J. Weiner , Jeffrey A. Newman , Kristin Madsen , R. Scott Barrows

We compute the flux of axions from Active Galactic Nuclei (AGN). Axions can be produced in the accretion disk by the Compton, Bremsstrahlung and Primakoff processes. We find that the axion luminosity due to these processes is negligible in…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 Pankaj Jain , Subhayan Mandal

The repeating changing-look active galactic nuclei (RCL AGNs) exhibit multiple appearances and disappearances of broad emission lines (BELs), whose underlying mechanism remains a puzzle. Expanding the sample of RCL AGNs is valuable for…

Astrophysics of Galaxies · Physics 2025-10-22 Qian Dong , Zhi-Xiang Zhang , Wei-Min Gu , Mouyuan Sun , Wei-Jian Guo , Zhen-Yi Cai , Jun-Xian Wang , Yong-Gang Zheng

It is commonly accepted that active galactic nuclei (AGN) have a strong impact upon the evolution of their host galaxies, but the processes by which they do so are not fully understood. We aim to further the understanding of AGN feeding and…

Astrophysics of Galaxies · Physics 2025-01-22 Sophie L. Robbins , Sandra I. Raimundo , Matthew A. Malkan

We measure the Eddington ratio distribution of local optical narrow-line active galactic nuclei (AGN) as a function of host galaxy properties, as a potential test of galaxy formation theories of AGN feedback. We extract central…

Astrophysics of Galaxies · Physics 2026-05-11 Michael R. Blanton , Arjun Suresh , Kyle B. Westfall , Dou Liu , John Moustakas

We explore possible physical origin of correlation between radio wave and very-high-energy neutrino emission in active galactic nuclei (AGN), suggested by recently reported evidence for correlation between neutrino arrival directions and…

High Energy Astrophysical Phenomena · Physics 2021-02-03 Andrii Neronov , Dmitry Semikoz

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

IceCube observations point to Active Galactic Nuclei (AGN) as promising contributors to the observed astrophysical neutrino flux. Close to the central black hole, protons can be accelerated through magnetic reconnection to very high…

High Energy Astrophysical Phenomena · Physics 2026-05-13 D. Karavola , M. Petropoulou , D. F. G. Fiorillo , A. Georgakakis , L. Comisso , L. Sironi

Active galactic nuclei (AGN) are a promising source for high-energy astrophysical neutrinos (HEANs). By the end of 2022, the Vera C. Rubin Observatory (VRO) will begin to observe $\gtrsim10$ million AGN with a regular and high cadence.…

High Energy Astrophysical Phenomena · Physics 2022-07-13 Cyril Creque-Sarbinowski , Marc Kamionkowski , Bei Zhou

The $\gamma$-ray astronomy in time domain has been by now progressed further as the variabilities of Active Galactic Nuclei (AGNs) on different timescales have been reported a lot. We study the $\gamma$-ray variabilities of 23 jetted AGNs…

High Energy Astrophysical Phenomena · Physics 2022-05-25 Haiyun Zhang , Dahai Yan , Li Zhang

The changing-look active galactic nucleus (CL-AGN), an extraordinary subpopulation of supermassive black holes, has attracted growing attention for understanding its nature. We present an analysis of the spectral properties of 203…

Astrophysics of Galaxies · Physics 2025-10-13 Yu-Heng Shen , Kai-Xing Lu , Wei-Jian Guo , Sha-Sha Li , Hai-Cheng Feng , Zhang Yue , Wen-Zhe Xi , Jian-Guo Wang , Jin-Ming Bai

The inter-band lags among the optical broad-band continua of active galactic nuclei (AGNs) have been intensively explored over the past decade. However, the nature of the lags remains under debate. Here utilizing two distinct scenarios for…

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