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相关论文: Accretion Disk Size Measurements of Active Galacti…

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Active galactic nuclei (AGN) have been observed to vary stochastically with 10-20 rms amplitudes over a range of optical wavelengths where the emission arises in an accretion disk. Since the accretion disk is unlikely to vary coherently,…

宇宙学与河外天体物理 · 物理学 2011-01-04 Jason Dexter , Eric Agol

Active galactic nuclei (AGN) are powered by the accretion of disks of gas onto supermassive black holes (SMBHs). Stars and stellar remnants orbiting the SMBH in the nuclear star cluster (NSC) will interact with the AGN disk. Orbiters…

星系天体物理 · 物理学 2020-11-02 Gaia Fabj , Syeda S. Nasim , Freddy Caban , K. E. Saavik Ford , Barry McKernan , Jillian M. Bellovary

Interband lags in the optical continua of active galactic nuclei (AGN) have been observed over years of monitoring, yet their physical origins remain unclear. While variable interband lags have been found in a few individual AGN…

星系天体物理 · 物理学 2025-07-08 Zhen-Bo Su , Zhen-Yi Cai , Hengxiao Guo , Mouyuan Sun , Jun-Xian Wang

Accretion disk winds are commonly observed in active galactic nuclei (AGN). The winds may be associated with the changing spectral properties of such sources, yet such connections have not been studied in detail so far. This paper presents…

星系天体物理 · 物理学 2025-04-29 Hagai Netzer

Variable continuum emission from AGN can be used to probe the structure of their accretion disks via reverberation mapping. Assuming a variable, hot inner light source irradiates the surrounding accretion disk, time delays between different…

Active galactic nuclei (AGN) light curves observed with different wavebands show that the variability in longer wavelength bands lags the variability in shorter wavelength bands. Measuring these lags, or reverberation mapping, is used to…

高能天体物理现象 · 物理学 2023-11-21 Amy Secunda , Yan-Fei Jiang , Jenny E. Greene

We present soft X-ray variability time-scales for 65 active galactic nuclei (AGNs) derived from ROSAT/PSPC pointing data. For these 65 objects with obvious exponential increasing or decreasing patterns in their light curves, we use the…

天体物理学 · 物理学 2009-11-07 W. Bian , Y. Zhao

We use a high-temperature chemical network to derive the molecular abundances in axisymmetric accretion disk models around active galactic nuclei (AGNs) within 100 pc using simple radial and vertical density and temperature distributions…

星系天体物理 · 物理学 2015-06-12 Nanase Harada , Todd A. Thompson , Eric Herbst

We present the latest results of a semi-analytic model of galaxy formation, "New Numerical Galaxy Catalogue", which is combined with large cosmological N-body simulations. This model can reproduce statistical properties of galaxies at z <…

This paper sets out to measure the timescale of quasar variability with a view to new understanding of the size of accretion discs in active galactic nuclei. Previous attempts to measure such timescales have been based on sparsely sampled…

天体物理学 · 物理学 2009-11-11 M. R. S. Hawkins

Accretion disks around stellar-mass black holes offer unique opportunities to study the fundamental physics of standard thin disks, super-Eddington disks, and structure that may be connected to flux variability. These local analogues of…

高能天体物理现象 · 物理学 2019-03-12 J. M. Miller , D. Barret , E. Cackett , M. Diaz Trigo , C. Done , E. Gallo , J. Kaastra , C. Motch , C. Pinto , G. Ponti , N. Webb , A. Zoghbi

The optical-ultraviolet continuum from active galactic nuclei (AGN) seem to originate from optically thick and/or thin disks, and occasionally from associated circumnuclear starburst regions. These different possible origins can, in…

天体物理学 · 物理学 2007-05-23 A. Yonehara , S. Mineshige , J. Fukue , M. Umemura , E. L. Turner

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…

高能天体物理现象 · 物理学 2025-07-14 Rong Du , Luis C. Ho , Yuanze Ding , Ruancun Li

Warped accretion discs in Active Galactic Nuclei (AGN) exert a torque on the black hole that tends to align the rotation axis with the angular momentum of the outer disc. We compute the magnitude of this torque by solving numerically for…

天体物理学 · 物理学 2009-10-31 Priyamvada Natarajan , Philip J. Armitage

Variability of active galactic nuclei (AGNs) has long been servicing as an essential avenue of exploring the accretion physics of black hole (BH). There are two commonly used methods for analyzing AGN variability. First, the AGN…

星系天体物理 · 物理学 2024-07-04 Zhen-Bo Su , Zhen-Yi Cai , Mouyuan Sun , Hengxiao Guo , Wei-Min Gu , Jun-Xian Wang

Stellar-mass compact objects (COs) embedded in active galactic nucleus (AGN) discs are commonly assumed to accrete via Bondi or Bondi-Hoyle-Lyttleton (BHL) prescriptions, neglecting gas angular momentum. We show that differential rotation…

高能天体物理现象 · 物理学 2025-11-19 Cheng-Liang Jiao , Liying Zhu , Er-gang Zhao , Jia Zhang

Active Galactic Nuclei (AGN) vary in their brightness across all wavelengths. Moreover, longer wavelength ultraviolet - optical continuum light curves appear to be delayed with respect to shorter wavelength light curves. A simple way to…

星系天体物理 · 物理学 2016-01-27 David Starkey , Keith Horne , Carolin Villforth

Compact objects are expected to exist in the accretion disks of supermassive black holes (SMBHs) in active galactic nuclei (AGNs), and in the presence of such a dense environment ($\sim 10^{14}\,{\rm cm^{-3}}$), they will form a new kind of…

高能天体物理现象 · 物理学 2021-04-21 Jian-Min Wang , Jun-Rong Liu , Luis C. Ho , Pu Du

A recent approach to simulating localized feedback from active galactic nuclei by Power et al. (2011) uses an accretion disc particle to represent both the black hole and its accretion disc. We have extrapolated and adapted this approach to…

宇宙学与河外天体物理 · 物理学 2015-06-12 James Wurster , Rob J. Thacker