Erratum: “Ultraviolet Continuum, Physical Conditions, and Filling Factor in Active Galactic Nuclei” (ApJ, 587, 562 [2003])

ABSTRACT In this manuscript, an interesting blue active galactic nuclei (AGNs) SDSS J154751.94+025550 (=SDSS J1547) is reported with very different line profiles of broad Balmer emission lines: double-peaked broad H β but single-peaked broad H α. SDSS J1547 is the first AGN with detailed discussions on very different line profiles of the broad Balmer emission lines, besides the simply mentioned different broad lines in the candidate for a binary black hole (BBH) system in SDSS J0159+0105. The very different line profiles of the broad Balmer emission lines can be well explained by different physical conditions to two central BLRs in a central BBH system in SDSS J1547. Furthermore, the long-term light curve from CSS can be well described by a sinusoidal function with a periodicity about 2159 d, providing further evidence to support the expected central BBH system in SDSS J1547. Therefore, it is interesting to treat different line profiles of broad Balmer emission lines as intrinsic indicators of central BBH systems in broad line AGN. Under assumptions of BBH systems, 0.125 per cent of broad-line AGN can be expected to have very different line profiles of broad Balmer emission lines. Future study on more broad line AGN with very different line profiles of broad Balmer emission lines could provide further clues on the different line profiles of broad Balmer emission lines as indicator of BBH systems.

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Intrinsic physical conditions and structure of relativistic jets in active galactic nuclei

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stu2587 ◽

2015 ◽

Vol 447 (3) ◽

pp. 2726-2737 ◽

Cited By ~ 19

Author(s):

E. E. Nokhrina ◽

V. S. Beskin ◽

Y. Y. Kovalev ◽

A. A. Zheltoukhov

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Relativistic Jets ◽

Physical Conditions

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Composite Models: A Tool for Interpreting the Emission-Line Spectra of Active Galactic Nuclei

Symposium - International Astronomical Union ◽

10.1017/s0074180900141178 ◽

1989 ◽

Vol 134 ◽

pp. 316-317

Author(s):

S.M. Viegas-Aldrovandi ◽

M. Contini

Keyword(s):

Energy Source ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Emission Lines ◽

Additional Energy ◽

Physical Conditions ◽

Dilute Gas ◽

Composite Models ◽

Line Widths ◽

Narrow Emission

In the last decade, emission-lines from a large number of active galactic nuclei (AGN) have been observed. Most of the models built to explain the observed narrow emission-lines are based on photoionization. Although these photoionization models account for the observed general features, many points remain unexplained and several authors suggest an additional energy source (Ferland and Mushotzky 1984, Ferland and Osterbrock 1986, Stasinska 1984, Viegas-Aldrovandi and Gruenwald 1988). Another possible explanation is suggested by the emitting cloud motions, which account for the observed line widths. If the clouds are moving throughout a dilute gas (n0 ≃ 300 cm−3), a shock can develop. Then, the physical conditions in the cloud are determined by the coupled effect of photoionization and shock hydrodynamics.

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AGN Disk Diagnostics

Highlights of Astronomy ◽

10.1017/s1539299600019304 ◽

1998 ◽

Vol 11 (2) ◽

pp. 964-967

Author(s):

R. D. Blandford

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

Mass Measurement ◽

Galactic Nuclei ◽

Second Order ◽

Accurate Mass Measurement ◽

Accurate Mass ◽

Central Black Hole ◽

Physical Conditions

The discovery of megamasers in nearby active galactic nuclei (AGN) is an unexpected boon for AGN researchers. The most immediate benefit, brought out in observations of NGC4258 (Miyoshi et al 1995, Moran, these proceedings) is that it allows an accurate mass measurement for the central black hole, in this case of 3.6 x 107 M⊙, with unprecedented accuracy. (I shall not belabor the point that we have not proven rigorously that it is a black hole because this is surely on much firmer footing than what follows!) Masers also allow us to discover second order features of the kinematics, specifically that the disk is warped. Thirdly, and this is what I have been asked to review here, it should enable us to choose between several possible accretion modes by treating masers as diagnostic probes of physical conditions in the disk.

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Physical Conditions in the Central Region, and the Nature of the Engine

Highlights of Astronomy ◽

10.1017/s1539299600005529 ◽

1983 ◽

Vol 6 ◽

pp. 511-524 ◽

Cited By ~ 1

Author(s):

A. Cavaliere

Keyword(s):

Active Galactic Nuclei ◽

Radiation Source ◽

Galactic Nuclei ◽

Primary Source ◽

Gravitational Energy ◽

Characteristic Change ◽

Cosmological Time ◽

Compact Mass ◽

Physical Conditions ◽

Prime Movers

AbstractThe phenomena associated with Active Galactic Nuclei raise three main astrophysical problems: (1) the nature of the primary source of energy; (2) the physical conditions within the radiation source; (3) the nature of the population evolution over cosmological time-scales.I shall outline the links between (1) and (2), (1) and (3), that briefly go as follows. The Prime Mover is very likely to be a converter of gravitational energy in a very compact mass configuration. The associated radiation source, if it is also very compact, is so efficient and loss-dominated as to require specific conditions for the power transport and supply to the radiating particles: collisionless, effected by electromagnetic fields coherent on scales collective or macroscopic, to the point of producing at times anisotropic bulk motions. Very compact Prime Movers working at high regimes need also a compact mass supply; the output from these compound engines undergoes a characteristic change that accounts for the type of population evolutions of the associated sources.

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A Photo-Ionization Method for Black Hole Mass Estimation in Quasars

Open Astronomy ◽

10.1515/astro-2017-0311 ◽

2011 ◽

Vol 20 (3) ◽

Cited By ~ 1

Author(s):

Paola Marziani ◽

C. Alenka Negrete ◽

Deborah Dultzin ◽

Jack W. Sulentic

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Compact Object ◽

Broad Line ◽

Line Profiles ◽

Line Broadening ◽

Physical Conditions ◽

Ionization Method ◽

The Masses ◽

Photo Ionization

AbstractDetermining the masses of the central compact object believed to power all active galactic nuclei is relevant to our understanding of their evolution and of their inner workings. Keys to present-day mass estimates are: (1) the assumption of line broadening due to virial motion of the emitting gas, (2) an estimate of the distance of broad-line emitting gas from the central compact object, and (3) a measure of the AGN luminosity. We discuss the merits and the limitations of an alternative method based on estimates of physical conditions in the broad line emitting region derived from an appropriate multi-component analysis of emission line profiles. This ‘photo-ionization method’, applied to UV intermediate-ionization lines appears to be promising for at least a sizable population of high-z quasars.

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5.13. High-density-and-temperature circumnuclear molecular torus in M51

Symposium - International Astronomical Union ◽

10.1017/s0074180900084758 ◽

1998 ◽

Vol 184 ◽

pp. 237-238

Author(s):

S. Matsushita ◽

K. Kohno ◽

B. Vila-Vilaro ◽

R. Kawabe ◽

T. Tosaki

Keyword(s):

Active Galactic Nuclei ◽

Molecular Clouds ◽

Galactic Nuclei ◽

Active Galaxies ◽

High Density ◽

Molecular Gas ◽

Physical Conditions

It is very important to know the physical conditions of circumnuclear molecular gas in order to understand the nature of Active Galactic Nuclei (AGN), since the circumnuclear molecular gas in active galaxies might be directly affected by or is affecting the activity of nucleus. To investigate the physical conditions of the molecular clouds in detail, multi-line observations with millimeter arrays are essential.

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