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Related papers: Explaining the Broad-line Region through photoioni…

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We consider photometric reverberation mapping, where the nuclear continuum variations are monitored via a broad-band filter and the echo of emission line clouds of the broad line region (BLR) is measured with a suitable narrow-band (NB)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 F. Pozo Nuñez , M. Haas , M. Ramolla , C. Bruckmann , C. Westhues , R. Chini , K. Steenbrugge , R. Lemke , M. Murphy , W. Kollatschny

We quantitatively assess, by means of comprehensive numerical simulations, the ability of broad-band photometric surveys to recover the broad emission line region (BLR) size in quasars under various observing conditions and for a wide range…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-25 Doron Chelouche , Ohad Shemmer , Gabriel I. Cotlier , Aaron J. Barth , Stephen E. Rafter

It is know that most of the clouds producing associated absorption in the spectra of AGNs and quasars do not completely cover the background source (continuum + broad emission line region, BLR). We note that the covering factor derived for…

Astrophysics · Physics 2009-10-31 R. Srianand , S. Shankaranarayanan

We present a new model to explain the appearance of red/blue-shifted broad low-ionization emission lines, especially emission lines in optical band, which is commonly considered as an indicator of radial motion of the line emitting gas in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Xue-GUang Zhang , Deborah Dultzin , Ting-Gui Wang , Guinevere Kaufmann

In this paper I present evidence suggesting that the absence or presence of Hidden Broad Line Regions (HBLRs) in Seyfert 2 galaxies is regulated by the rate at which matter accretes onto a central supermassive black hole, in units of…

Astrophysics · Physics 2007-05-23 F. Nicastro , A. Martocchia , G. Matt

Quasars show a remarkable degree of atomic emission line-broadening, an observational feature which, in conjunction with a radial distance estimate for this emission from the nucleus is often used to infer the mass of the central…

Models of active galactic nuclei often invoke a close physical association between the broad-line region and the accretion disk. We evaluate this theoretical expectation by investigating the relationship between the inclination angle of the…

High Energy Astrophysical Phenomena · Physics 2025-07-14 Rong Du , Luis C. Ho , Yuanze Ding , Ruancun Li

We study the broad emission line blazars detected in the gamma-ray band by the Large Area Telescope onboard the Fermi satellite and with the optical spectrum studied by Shaw et al. (2012, 2013). The observed broad line strength provides a…

High Energy Astrophysical Phenomena · Physics 2015-06-23 G. Ghisellini , F. Tavecchio

We study the relation between the metallicity of quasar broad line region (BLR) and black hole (BH) mass ($10^{7.5}M_{\odot} \sim 10^{10}M_{\odot}$) and quasar bolometric luminosity ($10^{44.6}erg/s \sim 10^{48} erg/s$) using a sample of…

Astrophysics of Galaxies · Physics 2018-07-18 Fei Xu , Fuyan Bian , Yue Shen , Wenwen Zuo , Xiaohui Fan , Zonghong Zhu

In this manuscript, an oversimplified model is proposed for the first time to explain the different variability trends in the observed broad H$\alpha$ emission line luminosity $L_{H\alpha}(t)$ and in the TDE model determined bolometric…

Astrophysics of Galaxies · Physics 2024-11-20 XueGuang Zhang

It is known that the dependence of the emission-line luminosity of a typical cloud in the active galactic nuclei broad-line regions (BLRs) upon the incident flux of ionizing continuum can be nonlinear. We study how this nonlinearity can be…

Astrophysics · Physics 2009-11-13 Alexander V. Melnikov , Ivan I. Shevchenko

Hubble Space Telescope (HST) spectroscopy of the Seyfert 1.5 galaxy, NGC 3227, confirms previous reports that the broad H-alpha emission line flux is time variable, decreasing by a modest ~ 11% between 1999 and 2000 in response to a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Nick Devereux

The 1-100 pc region embedding long-duration gamma-ray bursts (lGRBs) has been hitherto unexplored, as extremely high ionisation by the GRB prevents application of optical absorption spectroscopy on such distances. We show that the GRB…

High Energy Astrophysical Phenomena · Physics 2026-02-17 Aishwarya Linesh Thakur , Luigi Piro , Alfredo Luminari , Fabrizio Nicastro , Sandra Savaglio , Yair Krongold , Bruce Gendre

The reverberation mapping (RM) technique has seen wide applications in probing geometry and kinematics of broad-line regions (BLRs) and measuring masses of supermassive black holes (SMBHs) in active galactic nuclei. However, the key…

Astrophysics of Galaxies · Physics 2024-12-17 Yan-Rong Li , Jian-Min Wang

We present results from very high signal-to-noise spectropolarimetric observations of the Seyfert 1 galaxy NGC 3783. Position Angle (PA) changes across the Balmer lines show that the scatterer is resolving the Broad-Emission Line Region…

Astrophysics · Physics 2007-05-23 P. Lira , M. Kishimoto , A. Robinson , S. Young , D. Axon , M. Elvis , A. Lawrence , B. Peterson

The effective size of Broad Line Region (BLR), so-called the BLR radius, in galaxies with active galactic nuclei (AGN) scales with the source luminosity. Therefore by determining this location either observationally through reverberation…

Astrophysics of Galaxies · Physics 2020-04-07 Mohammad-Hassan Naddaf , Bozena Czerny , Ryszard Szczerba

We present a brief description of a model for the broad emission line region (BELR) in quasars, which is supported by analysis of CIV and other emission lines in the spectra of high-z SDSS quasars. Specifically we consider a two-component…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-13 Gordon T. Richards

Context. Dust in active galactic nuclei is clearly present right outside the broad-line region (BLR) in the form of a dusty molecular torus. However, some models of the BLR predict that dust may also exist within the BLR. Aims. We study the…

Black hole (BH) mass of Type I active galactic nuclei (AGN) can be measured or estimated through either reverberation mapping (RM) or empirical $R-L$ relation, however, both of them suffer from uncertainties of the virial factor ($f_{\rm…

Astrophysics of Galaxies · Physics 2017-11-15 Yu-Yang Songsheng , Jian-Min Wang