scholarly journals Spectropolarimetry of Seyfert 1 galaxies with equatorial scattering: black hole masses and broad-line region characteristics

2018 ◽  
Vol 482 (4) ◽  
pp. 4985-4999 ◽  
Author(s):  
V L Afanasiev ◽  
L Č Popović ◽  
A I Shapovalova
Keyword(s):  
Black Hole ◽  
Broad Line ◽  
Broad Line Region ◽  
Line Region ◽  
Black Hole Masses

A Photoionization Method for Estimating Black Hole Masses in Quasars

2018 ◽  
Vol 14 (S342) ◽  
pp. 270-271
Author(s):  
C. Alenka Negrete ◽  
Deborah Dultzin ◽  
Paola Marziani ◽  
Jack W. Sulentic ◽  
M. L. Martínez-Aldama
Keyword(s):  
Black Hole ◽  
High Redshift ◽  
Broad Line ◽  
Reverberation Mapping ◽  
Physical Conditions ◽  
Broad Line Region ◽  
Supermassive Black Hole ◽  
Line Region ◽  
Black Hole Masses

AbstractWe present a method that uses photoionization codes (CLOUDY) to estimate the supermassive black hole masses (MBH) for quasars at low and high redshift. This method is based on the determination of the physical conditions of the broad line region (BLR) using observational diagnostic diagrams from line ratios in the UV. We also considered that the density and metallicity of the BLR in quasars at high z could be different from those at the nearby Universe. The computed black hole masses obtained using this method are in agreement with those derived from the method of reverberation mapping.

scholarly journals Reverberation Mapping Measurements of Black Hole Masses and Broad-line Region Kinematics in Mrk 817 and NGC 7469

2021 ◽  
Vol 918 (2) ◽  
pp. 50
Author(s):  
Kai-Xing Lu ◽  
Jian-Guo Wang ◽  
Zhi-Xiang Zhang ◽  
Ying-Ke Huang ◽  
Liang Xu ◽  
...  
Keyword(s):  
Black Hole ◽  
Broad Line ◽  
Reverberation Mapping ◽  
Broad Line Region ◽  
Line Region ◽  
Black Hole Masses ◽  
Ngc 7469

scholarly journals THE LICK AGN MONITORING PROJECT: BROAD-LINE REGION RADII AND BLACK HOLE MASSES FROM REVERBERATION MAPPING OF Hβ

2009 ◽  
Vol 705 (1) ◽  
pp. 199-217 ◽  
Author(s):  
Misty C. Bentz ◽  
Jonelle L. Walsh ◽  
Aaron J. Barth ◽  
Nairn Baliber ◽  
Vardha Nicola Bennert ◽  
...  
Keyword(s):  
Black Hole ◽  
Broad Line ◽  
Reverberation Mapping ◽  
Broad Line Region ◽  
Line Region ◽  
Black Hole Masses

scholarly journals Modelling the AGN broad line region using single-epoch spectra – I. The test case of Arp 151

2019 ◽  
Vol 489 (2) ◽  
pp. 1899-1918 ◽  
Author(s):  
S I Raimundo ◽  
A Pancoast ◽  
M Vestergaard ◽  
M R Goad ◽  
A J Barth
Keyword(s):  
Black Hole ◽  
High Redshift ◽  
Monitoring Data ◽  
Test Case ◽  
Broad Line ◽  
Broad Line Region ◽  
Line Region ◽  
Single Epoch ◽  
Black Hole Masses ◽  
Dynamical Modelling

ABSTRACT We show that individual (single-epoch) spectra of active galactic nuclei (AGNs) can constrain some of the geometry and dynamics of the AGN broad line region. Studies of the cosmic influence of supermassive black holes are limited by the current large uncertainties in the determination of black hole masses. One dominant limitation is the unknown geometry, dynamics, and line-of-sight inclination of the broad line region, used to probe the central black hole mass. Recent progress has been made to constrain the spatial and kinematic structure of the broad line region using dynamical modelling of AGN monitoring data and an underlying physical model for the broad line region. In this work we test the ability of a modified version of this dynamical modelling code to constrain the broad line region structure using single-epoch spectra. We test our modelling code on single-epoch spectra of nearby Arp 151 by comparing our results with those obtained with monitoring data of this same object. We find that a significant fraction of the broad line region parameters can indeed be adequately constrained, with uncertainties that are comparable to, or at most a factor of approximately a few higher than those obtained from modelling of monitoring data. Considering the wealth of available single-epoch spectroscopic observations, this method is promising for establishing the overall AGN population trends in the geometry and dynamics of the broad line region. This method can be applied to spectra of AGNs at low and high redshift making it valuable for studies of cosmological black hole and AGN evolution.

scholarly journals Magnetization of AGN jets as imposed by leptonic models of luminous blazars

2014 ◽  
Vol 10 (S313) ◽  
pp. 85-86
Author(s):  
Mateusz Janiak ◽  
Marek Sikora ◽  
Rafal Moderski
Keyword(s):  
Black Hole ◽  
Kinetic Energy ◽  
Energy Flux ◽  
Broad Line ◽  
Jet Formation ◽  
Frequency Dependent ◽  
Broad Line Region ◽  
Line Region ◽  
Γ Ray ◽  
Dusty Torus

AbstractRecent measurements of frequency-dependent shift of radio-core locations indicate that the ratio of the magnetic to kinetic energy flux (the σ parameter) is of the order of unity. These results are consistent with predictions of magnetically-arrested-disk (MAD) models of a jet formation, but contradict the predictions of leptonic models of γ-ray production in luminous blazars. We demonstrate this discrepancy by computing the γ-ray-to-synchrotron luminosity ratio (the q parameter) as a function of a distance from the black hole for different values of σ and using both spherical and planar models for broad-line region and dusty torus. We find that it is impossible to reproduce observed q ≫ 1 for jets with σ ≥ 1. This may indicate that blazar radiation is produced in reconnection layers or in spines of magnetically stratified jets.

scholarly journals Modelling photometric reverberation data: a disk-like broad-line region and a potentially larger black hole mass for 3C 120

2014 ◽  
Vol 568 ◽  
pp. A36 ◽  
Author(s):  
F. Pozo Nuñez ◽  
M. Haas ◽  
M. Ramolla ◽  
C. Bruckmann ◽  
C. Westhues ◽  
...  
Keyword(s):  
Black Hole ◽  
Broad Line ◽  
Black Hole Mass ◽  
Broad Line Region ◽  
Line Region ◽  
3C 120

scholarly journals A Survey of QSO Emission Lines

1986 ◽  
Vol 119 ◽  
pp. 279-288
Author(s):  
Beverley J. Wills
Keyword(s):  
Black Hole ◽  
Good Description ◽  
Emission Lines ◽  
Broad Line ◽  
Physical Conditions ◽  
Broad Line Region ◽  
Heating Mechanism ◽  
Ionization Density ◽  
Line Region ◽  
High Temperature Gas

“Standard” photoionization models of the broad line region (BLR) consist of numerous small optically thick clouds of identical ionization, density, temperature and optical depth, moving under the influence of the gravity and radiation field of a 107–8 M⊙ black hole and confined by a high temperature gas. Such models have provided a good description of observed line strengths and widths with only very minor modification. Although photoionization remains the most important heating mechanism in the BLR, new observations point to a wider range of physical conditions and to clues about the geometric and dynamic arrangement of the emitting gas. I want to highlight the observations that have led us to this view.

scholarly journals Dusty origin of the Broad Line Region in active galaxies

2012 ◽  
Vol 8 (S290) ◽  
pp. 21-24
Author(s):  
Bozena Czerny ◽  
Krzysztof Hryniewicz ◽  
Janusz Kaluzny ◽  
Ishita Maity
Keyword(s):  
Black Hole ◽  
Active Galaxies ◽  
Emission Lines ◽  
Broad Line ◽  
Broad Line Region ◽  
Broad Emission ◽  
Line Region ◽  
Interesting Possibility ◽  
Considerable Complexity

AbstractThe most characteristic property of active galaxies, including quasars, are prominent broad emission lines. I will discuss an interesting possibility that dust is responsible for this phenomenon. The dust is known to be present in quasars in the form of a dusty/molecular torus which results in complexity of the appearance of active galaxies. However, this dust is located further from the black hole than the Broad Line Region. We propose that the dust is present also closer in and it is actually responsible for formation of the broad emission lines. The argument is based on determination of the temperature of the disk atmosphere underlying the Broad Line Region: it is close to 1000 K, independently from the black hole mass and accretion rate of the object. The mechanism is simple and universal but leads to a considerable complexity of the active nucleus surrounding. The understanding the formation of BLR opens a way to use it reliably - in combination with reverberation measurement of its size - as standard candles in cosmology.

scholarly journals The spatially resolved broad line region of IRAS 09149−6206

2020 ◽  
Vol 643 ◽  
pp. A154 ◽  
Author(s):  
◽  
A. Amorim ◽  
M. Bauböck ◽  
W. Brandner ◽  
Y. Clénet ◽  
...  
Keyword(s):  
Black Hole ◽  
Near Infrared ◽  
Time Lag ◽  
Calibration Method ◽  
Broad Line ◽  
Differential Phase ◽  
Broad Line Region ◽  
Line Region ◽  
Phase Calibration ◽  
Dust Distribution

We present new near-infrared VLTI/GRAVITY interferometric spectra that spatially resolve the broad Brγ emission line in the nucleus of the active galaxy IRAS 09149−6206. We use these data to measure the size of the broad line region (BLR) and estimate the mass of the central black hole. Using an improved phase calibration method that reduces the differential phase uncertainty to 0.05° per baseline across the spectrum, we detect a differential phase signal that reaches a maximum of ∼0.5° between the line and continuum. This represents an offset of ∼120 μas (0.14 pc) between the BLR and the centroid of the hot dust distribution traced by the 2.3 μm continuum. The offset is well within the dust sublimation region, which matches the measured ∼0.6 mas (0.7 pc) diameter of the continuum. A clear velocity gradient, almost perpendicular to the offset, is traced by the reconstructed photocentres of the spectral channels of the Brγ line. We infer the radius of the BLR to be ∼65 μas (0.075 pc), which is consistent with the radius–luminosity relation of nearby active galactic nuclei derived based on the time lag of the Hβ line from reverberation mapping campaigns. Our dynamical modelling indicates the black hole mass is ∼1 × 108 M⊙, which is a little below, but consistent with, the standard MBH–σ* relation.

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