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Using the stellar population synthesis, we model the stellar contribution for a sample of 110 double-peaked broad-lines AGNs from the Sloan Digital Sky Survey (SDSS). The stellar velocity dispersions ($\sigma_*$) are obtained for 52…

Astrophysics · Physics 2009-11-13 Wei-Hao Bian , Yan-Mei Chen , Qu-Sheng Gu , Jin-Min Wang

Massive black holes detected in the centers of many nearby galaxies are linearly correlated with the luminosity of the host bulge, the black hole mass being about 0.1% of the bulge mass. An even stronger relation exists between the BH mass…

Astrophysics · Physics 2007-05-23 Amri Wandel

The virial coefficient ($f$), which is meant to encapsulate broad-line region (BLR) geometry and kinematics, remains one of the largest sources of systematic uncertainty in black hole mass estimates for Active Galactic Nuclei (AGNs). While…

To tackle the still unsolved and fundamental problem of the role of Active Galactic Nuclei (AGN) feedback in shaping galaxies, in this work we implement a new physical treatment of AGN-driven winds into our semi-analytic model of galaxy…

Astrophysics of Galaxies · Physics 2023-06-28 N. Menci , F. Fiore , F. Shankar , L. Zanisi , C. Feruglio

We have measured the stellar velocity dispersions (\sigma_*) and estimated the central black hole (BH) masses for over 900 broad-line active galactic nuclei (AGNs) observed with the Sloan Digital Sky Survey. The sample includes objects…

Astrophysics · Physics 2009-06-23 J. Shen , D. E. Vanden Berk , D. P. Schneider , P. B. Hall

Based on the measured sizes of broad line region of the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift ($z > 0.5$) AGNs. First, using the…

Astrophysics · Physics 2009-11-13 Min-Zhi Kong , Xue-Bing Wu , Ran Wang , Jin-Lin Han

Reverberation mapping (RM) determines the mass of black holes (BH) in active galactic nuclei (AGNs) by resolving the BH gravitational sphere of influence in the time domain. Recent RM campaigns yielded direct BH masses through dynamical…

Context: Active Galactic Nuclei are highly variable emitters of electromagnetic waves from the radio to the gamma-ray regime. This variability may be periodic, which in turn could be the signature of a binary black hole. Systems of black…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Constanze Roedig , Thomas Burkart , Oliver Elbracht , Felix Spanier

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

In this work, we aim to further populate the low-mass regime of black hole (BH) scaling relations to better understand the formation and growth mechanisms of central supermassive BHs. We target six galaxies that have been previously…

Astrophysics of Galaxies · Physics 2025-07-28 Megan R. Sturm , Amy E. Reines , Jenny Greene , Sheyda Salehirad

We exploit our formula for the gravitational potential of finite size, power-law disks to derive a general expression linking the mass of the black hole in active galactic nuclei (AGN), the mass of the surrounding disk, its surface density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Jean-Marc Huré , Franck Hersant , Clément Surville , Naomasa Nakai , Thierry Jacq

Here we present the spectropolarimetric observations of a sample of 30 Type 1 AGNs and an analysis of the observed polarization in these AGNs. The observations have been performed with the 6-meter telescope of SAO RAS using the modified…

Astrophysics of Galaxies · Physics 2018-11-28 V. L. Afanasiev , L. C. Popovic , A. I. Shapovalova

We use a large, heterogeneous sample of local active galactic nuclei (AGN) that includes Seyfert 1s, Seyfert 2s and PG quasars to investigate for the first time the relation between black hole mass (M_BH) and mid-infrared nuclear emission.…

Astrophysics · Physics 2019-08-15 A. Alonso-Herrero , V. D. Ivanov , R. Jayawardhana , T. Hosokawa

It is shown that broad-line region (BLR) line profiles ranging from the classic "logarithmic" profile to double-peaked, disk-like profiles are readily explained by the distribution of BLR gas proposed by Gaskell, Klimek, & Nazarova (2007;…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-09 C. Martin Gaskell

Long-time-scale X-ray and optical variability is a key characteristic of AGN. Here, we summarise our current understanding of the X-ray and optical continuum variability of radio-quiet AGN and the relation between the two bands. We…

Astrophysics · Physics 2008-11-26 Philip Uttley , Ian M. McHardy

In the sixth of the series of papers reporting on a large reverberation mapping (RM) campaign of active galactic nuclei (AGNs) with high accretion rates, we present velocity-resolved time lags of H$\beta$ emission lines for nine objects…

Astrophysics of Galaxies · Physics 2016-03-23 Pu Du , Kai-Xing Lu , Chen Hu , Jie Qiu , Yan-Rong Li , Ying-Ke Huang , Fang Wang , Jin-Ming Bai , Wei-Hao Bian , Ye-Fei Yuan , Luis C. Ho , Jian-Min Wang

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

The profiles of the broad emission lines of active galactic nuclei (AGNs) and the time delays in their response to changes in the ionizing continuum ("lags") give information about the structure and kinematics of the inner regions of AGNs.…

High Energy Astrophysical Phenomena · Physics 2018-04-18 C. Martin Gaskell , Peter Z. Harrington

Along the last ten years, a general relativistic method has been developed to generate analytical expressions for the black hole (BH) parameters in terms of observables, namely the frequency shift of photons emitted by orbiting test…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Adriana González-Juárez , Alfredo Herrera-Aguilar

A common feature of Active Galactic Nuclei (AGN) is their random variations in brightness across the whole emission spectrum, from radio to $\gamma$-rays. Studying the nature and origin of these fluctuations is critical to characterising…

Astrophysics of Galaxies · Physics 2025-10-17 Mehdy Lefkir , Simon Vaughan , Daniela Huppenkothen , Phil Uttley , Vysakh Anilkumar