scholarly journals An Analysis of Broad Emission-Line Profiles from HST Data

1997 ◽  
Vol 159 ◽  
pp. 195-196
Author(s):  
Stephanie A. Snedden ◽  
C. Martin Gaskell
Keyword(s):  
Radial Velocity ◽  
Emission Line ◽  
Line Profile ◽  
B Value ◽  
Line Profiles ◽  
Broad Emission ◽  
Blue Wing ◽  
Broad Emission Line

AbstractWe have analyzed the HST FOS spectra of all quasars in the Stirpe (1990) high S/N line-profile sample and studied line-profile ratios as a function of radial velocity. Some quasars show no sign at all of NLR Lyα. We confirm that Hα is narrower than Lyα (after allowance for NLR contributions). The Lyα/Hα ratios in the cores of the broad lines are all close to or slightly less than case B and values predicted by single-cloud photoionization models. The Lyα/Hα ratio is surprisingly high in the blue wing. With only one exception, the ratios are equal to or greater than the case B value. Intrinsic reddening must be very small in most cases. We also briefly discuss other ratios.

scholarly journals The Kinematics of Quasar Broad Emission Line Regions Using a Disk-Wind Model

2017 ◽  
Vol 34 ◽  
Author(s):  
Suk Yee Yong ◽  
Rachel L. Webster ◽  
Anthea L. King ◽  
Nicholas F. Bate ◽  
Matthew J. O’Dowd ◽  
...  
Keyword(s):  
Emission Line ◽  
Line Profile ◽  
Inclination Angle ◽  
Opening Angle ◽  
Line Profiles ◽  
Wind Model ◽  
Disk Wind ◽  
Reverberation Mapping ◽  
Broad Emission ◽  
Line Region

AbstractThe structure and kinematics of the broad line region in quasars are still unknown. One popular model is the disk-wind model that offers a geometric unification of a quasar based on the viewing angle. We construct a simple kinematical disk-wind model with a narrow outflowing wind angle. The model is combined with radiative transfer in the Sobolev, or high velocity, limit. We examine how angle of viewing affects the observed characteristics of the emission line. The line profiles were found to exhibit distinct properties depending on the orientation, wind opening angle, and region of the wind where the emission arises.At low inclination angle (close to face-on), we find that the shape of the emission line is asymmetric, narrow, and significantly blueshifted. As the inclination angle increases (close to edge-on), the line profile becomes more symmetric, broader, and less blueshifted. Additionally, lines that arise close to the base of the disk wind, near the accretion disk, tend to be broad and symmetric. Single-peaked line profiles are recovered for the intermediate and equatorial wind. The model is also able to reproduce a faster response in either the red or blue sides of the line profile, consistent with reverberation mapping studies.

scholarly journals The Nature and Origin of Structure in Broad Emission Line Profiles

1997 ◽  
Vol 159 ◽  
pp. 193-194 ◽  
Author(s):  
C. Martin Gaskell ◽  
Stephanie A. Snedden
Keyword(s):  
Emission Line ◽  
The Other ◽  
Central Component ◽  
Balmer Line ◽  
Line Profiles ◽  
Broad Emission ◽  
Broad Emission Line

AbstractWe postulate that all structure in broad lines can be explained by a central component (at the systemic redshift) and the addition of two ‘displaced components’, one blueshifted and the other redshifted. We have been able to successfully classify all Balmer-line profiles on this basis. 3C 390.3-type objects are merely examples where the shifts of the displaced components are unusually large. We believe that the displaced peaks are less prominent in the UV lines because the higher ionization lines are broader.

scholarly journals Constraining the geometry and kinematics of the quasar broad emission line region using gravitational microlensing

2019 ◽  
Vol 629 ◽  
pp. A43 ◽  
Author(s):  
D. Hutsemékers ◽  
L. Braibant ◽  
D. Sluse ◽  
R. Goosmann
Keyword(s):  
Emission Line ◽  
Line Profile ◽  
Polar Wind ◽  
Disk Model ◽  
Continuum Source ◽  
Broad Emission ◽  
Gravitational Microlensing ◽  
Line Region ◽  
Broad Emission Line ◽  
Single Epoch

The quadruply lensed quasar HE0435−1223 shows a clear microlensing effect that affects differently the blue and red wings of the Hα line profile in its image D. To interpret these observations, and constrain the broad emission line region (BLR) properties, the effect of gravitational microlensing on quasar broad emission line profiles and their underlying continuum has been simulated considering representative BLR models and microlensing magnification maps. The amplification and distortion of the Hα line profile, characterized by a set of four indices, can be reproduced by the simulations. Although the constraints on the BLR models set by the observed single-epoch microlensing signal are not very robust, we found that flattened geometries (Keplerian disk and equatorial wind) can more easily reproduce the observed line profile deformations than a biconical polar wind. With an additional independent constraint on the size of the continuum source, the Keplerian disk model of the Hα BLR is slightly favored.

scholarly journals The Diversity of Broad Emission-Line Profiles

1997 ◽  
Vol 159 ◽  
pp. 197-198
Author(s):  
Giovanna M. Stirpe ◽  
Andrew Robinson ◽  
David J. Axon
Keyword(s):  
Simple Model ◽  
Emission Line ◽  
Power Law ◽  
Active Galaxies ◽  
Broad Line ◽  
Line Profiles ◽  
Broad Emission ◽  
Power Law Function ◽  
Broad Emission Line ◽  
Almost All

AbstractWe present preliminary results from a study of broad-line profiles in active galaxies. A simple model in which the emissivity is a broken power-law function of radius, and the BLR clouds emit anisotropically, yields very good fits to almost all the Ha profiles in our data base.

scholarly journals Long-term variability of the Broad Emission Line profiles in AGN

2009 ◽  
Vol 53 (7-10) ◽  
pp. 191-197 ◽  
Author(s):  
A.I. Shapovalova ◽  
L.Č. Popović ◽  
N.G. Bochkarev ◽  
A.N. Burenkov ◽  
V.H. Chavushyan ◽  
...  
Keyword(s):  
Emission Line ◽  
Line Profiles ◽  
Broad Emission ◽  
Broad Emission Line
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