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This is the second in a series of papers aiming to test how the mass ($M_{\rm BH}$), accretion rate ($\dot{M}$) and spin ($a_{*}$) of super massive black holes (SMBHs) determine the observed properties of type-I active galactic nuclei…

Astrophysics of Galaxies · Physics 2016-06-24 Julián E. Mejía-Restrepo , Benny Trakhtenbrot , Paulina Lira , Hagai Netzer , Daniel M. Capellupo

Extended narrow-line regions (NLRs) around active galactic nuclei (AGN) are shaped by the distribution of gas in the host galaxy and by the geometry of the circumnuclear obscuration, and thus they can be used to test the AGN unification…

A handful of well-studied Weak-Line Radio Galaxies (WLRGs) have been traditionally classified as Low Ionization Nuclear Emission-line Regions (LINERs), suggesting that these two groups of AGNs might be related. In this paper, we present new…

Astrophysics · Physics 2009-11-07 Karen T. Lewis , Michael Eracleous , Rita M. Sambruna

We report CFHT/SITELLE imaging Fourier Transform Spectrograph observations of the Brightest Cluster Galaxy (BCG) of galaxy cluster Abell 2390 at z=0.228. The BCG displays a prominent cone of emission in H$\alpha$, H$\beta$, [NII], and [OII]…

The broad emission lines (BELs) emitted by Active Galactic Nuclei respond to variations in the ionizing continuum emission from the accretion disk surrounding the central supermassive black hole (SMBH). This reverberation response provides…

Astrophysics of Galaxies · Physics 2025-07-22 Sara Rosborough , Andrew Robinson , Triana Almeyda , Daniel Humphrey , Madison Noll

[Abridged] Optically thick, geometrically thin accretion disks around supermassive black holes are thought to contribute to broad-line emission in type-1 active galactic nuclei (AGN). However, observed emission line profiles most often…

Here we present the results of the long-term (1995-2007) spectral monitoring of the broad line radio galaxy \object{3C~390.3}, a well known AGN with the double peaked broad emission lines, usually assumed to be emitted from an accretion…

Many studies have considered the roles of clouds, outflows, and turbulence in producing the broad emission and absorption lines in the spectra of active galactic nuclei (AGNs). However, these are often treated as separate or even competing…

Astrophysics of Galaxies · Physics 2019-12-10 Tim Waters , Hui Li

The majority of Little Red Dots (LRDs) hosting Active Galactic Nuclei (AGN) exhibits broad H$\alpha$ emission, which recent studies propose originates from scattering off free electrons within an ionized and dense medium embedding the Broad…

Astrophysics of Galaxies · Physics 2025-11-26 Matilde Brazzini , Francesco D'Eugenio , Roberto Maiolino , Ignas Juodžbalis , Xihan Ji , Jan Scholtz

A new model is presented which explains the origin of the broad emission lines observed in the LINER/Seyfert nucleus of M81 in terms of a steady state spherically symmetric inflow, amounting to 1 x 10^-5 Msun/yr, which is sufficient to…

Astrophysics · Physics 2009-11-13 Nick Devereux , Andrew Shearer

Active galactic nuclei (AGNs) have typically been discovered in massive galaxies of high metallicity. We attempt to increase the number of AGN candidates in low metallicity galaxies. We present VLT/UVES and archival VLT/FORS1 spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-29 Y. I. Izotov , N. G. Guseva , K. J. Fricke , G. Stasinska , C. Henkel , P. Papaderos

Adopting a spherically symmetric steady-state ballistic inflow as the kinematic model for the gas distribution responsible for producing the H{\alpha} emission line and a central black hole (BH) mass of 1.7 x10^6 M_sun, determined from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nick Devereux , Emily Heaton

A combined analysis of the profiles of the main broad quasar emission lines in both Hubble Space Telescope and optical spectra shows that while the profiles of the strong UV lines are quite similar, there is frequently a strong increase in…

Astrophysics · Physics 2017-02-22 Stephanie A. Snedden , C. Martin Gaskell

Iron K-alpha lines are key diagnostics of the central regions of AGN. Their profiles indicate that they are formed deep in the potential well of the central black hole, where extreme broadening and red shift occur. The profiles are most…

Astrophysics · Physics 2009-10-31 K. Nandra

The low-luminosity active galactic nuclei in NGC 3147, NGC 4203, and NGC 4579 have been imaged at four frequencies with the Very Long Baseline Array. The galaxies are unresolved at all frequencies, with size upper limits of $10^3-10^4$…

Astrophysics · Physics 2009-11-07 James S. Ulvestad , Luis C. Ho

We present evidence for X-ray line emitting and absorbing gas in the nucleus of the Broad-Line Radio Galaxy (BLRG), 3C 445. A 200ks Chandra LETG observation of 3C 445 reveals the presence of several highly ionized emission lines in the soft…

High Energy Astrophysical Phenomena · Physics 2015-05-20 J. N. Reeves , J. Gofford , V. Braito , R. Sambruna

We present new images of the coronal line region, as traced by [Si VII] 2.48 \um, in some of the nearest Seyfert 2 galaxies. In each of these galaxies, the coronal line emission comprises a bright, compact central source and extended…

Astrophysics · Physics 2009-11-13 M. Almudena Prieto , Olivier Marco , Jack Gallimore

Narrow Line Seyfert 1 galaxies represent a distinct category in the larger family of Type 1 Active Galactic Nuclei. The occurrence of emission line profiles not broader than 2000 km/s, combined with luminosity estimates comparable to those…

High Energy Astrophysical Phenomena · Physics 2011-06-14 G. La Mura , S. Ciroi , V. Cracco , D. Ilić , L. Č. Popović , P. Rafanelli

We present an analysis of the optical nuclear spectra from the active galactic nuclei (AGN) in a sample of giant low surface brightness (GLSB) galaxies. GLSB galaxies are extreme late type spirals that are large, isolated and poorly evolved…

Astrophysics of Galaxies · Physics 2017-08-23 Smitha Subramanian. , Ramya. S. , Mousumi Das. , Koshy George. , T. Sivarani , T. P. Prabhu

Using the Gemini Near-InfraRed Spectrograph (GNIRS), we have assembled a complete sample of 20 K-selected galaxies at 2.0<z<2.7 with high quality near-infrared spectra. As described in a previous paper, 9 of these 20 galaxies have strongly…