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Related papers: AGN Continuum Reverberation Mapping Based on Zwick…

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It has been shown that the luminosity of AGNs and the size of their broad line region obey a simple relation of the type R=a L^g, from faint Seyfert nuclei to bright quasars, allowing single-epoch determination of the central black hole…

Astrophysics · Physics 2009-11-13 D. Trevese , D. Paris , G. M. Stirpe , F. Vagnetti , V. Zitelli

Reverberation mapping probes the structure of the broad emission-line region (BLR) in active galactic nuclei (AGN). The kinematics of the BLR gas can be used to measure the mass of the central supermassive black hole. The main uncertainty…

Astrophysics of Galaxies · Physics 2015-09-23 Andreas Skielboe , Anna Pancoast , Tommaso Treu , Daeseong Park , Aaron J. Barth , Misty C. Bentz

The broadband spectral energy distribution (SED) of Active Galactic Nuclei (AGN) is investigated for a well-selected sample composed of $23$ Seyfert 1 galaxies observed simultaneously in the optical/UV and X-ray bands with the Neil Gehrels…

High Energy Astrophysical Phenomena · Physics 2019-06-12 Huaqing Cheng , Weimin Yuan , He-Yang Liu , A. A. Breeveld , Chichuan Jin , Bifang Liu

Broad emission lines in active galactic nuclei (AGNs) mainly arise from gas photoionized by continuum radiation from an accretion disk around a central black hole. The shape of the broad-line profile, described by ${\cal D}_{_{\rm…

Astrophysics of Galaxies · Physics 2016-02-17 Pu Du , Jian-Min Wang , Chen Hu , Luis C. Ho , Yan-Rong Li , Jin-Ming Bai

We have measured the wavelength-dependent lags between the X-ray, UV and optical bands in the high accretion rate ($L/L_{\rm Edd}\approx40\%$) Active Galactic Nucleus Mrk 110 during two intensive monitoring campaigns in February and…

High Energy Astrophysical Phenomena · Physics 2022-02-09 F. M. Vincentelli , I. McHardy , V. Hernández Santisteban , E. M. Cackett , J. Gelbord , Keith Horne , J. A. Miller , A. Lobban

We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on the 3-m Shane telescope at Lick Observatory from April 2016 to May 2017. Targeting active galactic nuclei (AGN) with…

Changing-look Active Galactic Nuclei (CL AGNs) exhibit drastic variations in broad emission lines (BELs), the mechanism of which remains unclear. Expanding the sample of CL AGNs is helpful to reveal the mechanism. This study aims to…

Astrophysics of Galaxies · Physics 2025-04-24 Qian Dong , Zhi-Xiang Zhang , Wei-Min Gu , Mouyuan Sun , Yong-Gang Zheng

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

We model the broadband (optical/UV and X-ray) continuum spectrum of the "changing-look" active galactic nucleus (AGN) Mrk 1018 as it fades from Seyfert 1 to 1.9 in $\sim 8$ years. The brightest spectrum, with Eddington ratio $L/L_{\rm…

Astrophysics of Galaxies · Physics 2018-08-08 Hirofumi Noda , Chris Done

We present improved black hole masses for 35 active galactic nuclei (AGNs) based on a complete and consistent reanalysis of broad emission-line reverberation-mapping data. From objects with multiple line measurements, we find that the…

We present models of the H$\beta$-emitting broad-line region (BLR) in seven Seyfert 1 galaxies from the Lick AGN (Active Galactic Nucleus) Monitoring Project 2011 sample, drawing inferences on the BLR structure and dynamics as well as the…

The truncation of an optically thick, geometrically thin accretion disk is investigated in the context of low luminosity AGN (LLAGN). We generalize the disk evaporation model used in the interpretative framework of black hole X-ray binaries…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Ronald E. Taam , B. F. Liu , W. Yuan , E. Qiao

We use a recently proposed luminosity distance measure for relatively nearby active galactic nuclei (AGNs) to test the predicted expansion of the Universe in the R_h=ct and LCDM cosmologies. This comparative study is particularly relevant…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Fulvio Melia

This is the third in a series of papers reporting on a large reverberation-mapping campaign aimed to study the properties of active galactic nuclei (AGNs) with high accretion rates. We present new results on the variability of the optical…

Astrophysics of Galaxies · Physics 2015-05-27 Chen Hu , Pu Du , Kai-Xing Lu , Yan-Rong Li , Fang Wang , Jie Qiu , Jin-Ming Bai , Shai Kaspi , Luis C. Ho , Hagai Netzer , Jian-Min Wang

Massive molecular clouds have been discovered in massive elliptical galaxies at the center of galaxy clusters. Some of this cold gas is expected to flow in the central supermassive black holes and activate galactic nucleus (AGN) feedback.…

Astrophysics of Galaxies · Physics 2023-08-09 Yutaka Fujita , Takuma Izumi , Nozomu Kawakatu , Hiroshi Nagai , Ryo Hirasawa , Yu Ikeda

Context. Continuum time delays from accretion disks in active galactic nuclei (AGN) has been proposed long time ago as a tool for measuring distances to the monitored sources. However, the method faces serious problems as a number of…

Astrophysics of Galaxies · Physics 2023-03-01 Vikram Kumar Jaiswal , Raj Prince , Swayamtrupta Panda , Bożena Czerny

Reverberation mapping (RM) is one of the most efficient ways to investigate the broad-line region around the central supermassive black holes of active galactic nuclei (AGNs). A common way of performing the RM is to perform a long term…

Astrophysics of Galaxies · Physics 2019-11-06 Joonho Kim , Myungshin Im , Changsu Choi , Sungyong Hwang

According to the standard model, an active galactic nucleus (AGN) consists of an inner accretion disk with a jet around a central massive black hole, and a number of outer broad line regions (BLRs) and narrow line regions (NLRs). The…

Astrophysics · Physics 2009-11-13 W. Bian

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in…