Emission-line profiles from a relativistic accretion disk and the role of its multiple images

1994 ◽  
Vol 435 ◽  
pp. 55 ◽  
Author(s):  
G. Bao ◽  
P. Hadrava ◽  
E. Ostgaard
Keyword(s):  
Emission Line ◽  
Accretion Disk ◽  
Line Profiles ◽  
Multiple Images

scholarly journals Interacting Nuclei in Distant Galaxies

1990 ◽  
Vol 124 ◽  
pp. 251-253
Author(s):  
Wei Zheng ◽  
Steven A. Grandi
Keyword(s):  
Emission Line ◽  
Active Galactic Nuclei ◽  
Accretion Disk ◽  
Outer Part ◽  
Line Emission ◽  
Galactic Nuclei ◽  
Balmer Line ◽  
Line Profiles ◽  
Double Peaks ◽  
Distant Galaxies

The interaction of galaxies not only occurs in galactic scales, but also may be linked to the binary cores in active galactic galaxies. The presence of a binary in the center of galaxies was suggested by Begelman, Blandford and Rees (1980). Gaskell (1983) suggests that supermassive binaries may account for the observed structure of emission line profiles such as double peaks displaced by a significant velocity difference. Collin-Souffrin, et al. (1986) argue that line emission may be formed in the outer part of an accretion disk. The resultant profile, as expected from rotational motion, would be very broad and often possess a double-horn shape. However, the emission line profiles in most active galactic nuclei do not share such a resemblance, and there are only two reported cases, 3C390.3 (Pérez et al. 1987) and Arp102B (Chen, Halpern and Filippenko 1989), in which the broad Balmer line profile may be of such a shape. Therefore, the assumption for accretion disk is to be verified with care.

scholarly journals The broad line emission from the AGN 3C 390.3: complex broad-line region and perturbation in accretion disk

2012 ◽  
Vol 8 (S290) ◽  
pp. 205-206
Author(s):  
Ilić Dragana ◽  
Luka Č. Popović ◽  
Alla I. Shapovalova ◽  
Alexander N. Burenkov ◽  
Vahram H. Chavushyan ◽  
...  
Keyword(s):  
Emission Line ◽  
Accretion Disk ◽  
Radio Galaxy ◽  
Dominant Role ◽  
Line Emission ◽  
Broad Line ◽  
Line Profiles ◽  
Broad Emission ◽  
Line Region ◽  
Present Part

AbstractFrom 13-years of the spectral optical monitoring of a well-known broad-line radio galaxy 3C 390.3 we concluded that the geometry of the broad emission-line region is complex, while still the main part of the emission is coming from the accretion disk. Here we present part of the analysis of the broad Hα and Hβ emission lines, which are showing highly variable double-peaked profiles during the monitoring period (1995-2007), with the aim to probe the accretion disk properties. The disk-like geometry plays a dominant role, but the variability of Hα and Hβ line profiles and intensities shows a presence of an additional emission-line region, that has a different nature for different periods, e.g. in one period the observed variation can be well modeled if one assumes changes in position and size of the emitting disk along the accretion disk.

scholarly journals The Orbital Period of G61-29

1979 ◽  
Vol 53 ◽  
pp. 453-457 ◽  
Author(s):  
R. E. Nather ◽  
E. L. Robinson ◽  
R. J. Stover
Keyword(s):  
Emission Line ◽  
Accretion Disk ◽  
Orbital Period ◽  
High Speed ◽  
Orbital Motion ◽  
Close Binary System ◽  
Close Binary ◽  
Line Profiles ◽  
High Speed Photometry ◽  
Emission Line Spectrum

The proper-motion star G61-29 (Giclas et al 1971) was discovered to have an emission-line spectrum consisting entirely of helium by Burbidge and Strittmatter (1971), who noted that the very broad lines (ca. 32 Å at λ4471) seemed to have variable profiles. Warner (1972) suggested that the star might be a close binary system, with the emission lines arising from an accretion disk surrounding a white dwarf, and searched for evidence of binary motion using high speed photometry. He suggested a tentative orbital period of 6h 16m, which subsequent observations were unable to confirm. Smak (1975) studied the star spectroscopically and agreed with Warner’s accretion disk hypothesis based on his analysis of the emission line profiles, but was also unable to derive evidence of orbital motion from his spectra, which were exposed for about 40 minutes each. Greenstein et al.(1977) also observed profile variations in spectra with shorter exposures, but evidently did not search for periodicities.

scholarly journals How Does One Detect An Accretion Disk?

1992 ◽  
Vol 151 ◽  
pp. 175-183
Author(s):  
Ronald H. Kaitchuck
Keyword(s):  
Binary System ◽  
Emission Line ◽  
Accretion Disk ◽  
Variable Stars ◽  
Emission Lines ◽  
New Technique ◽  
Cataclysmic Variable ◽  
Line Profiles ◽  
Doppler Tomography ◽  
History Of

The history of the first detection of an accretion disk in a interacting binary system is presented. The nature of transient and permanent disks in Algol-type binaries is discussed as are the problems associated with the interpretation of emission line profiles from the disks in cataclysmic variable stars. The new technique of eclipse mapping from continuum photometry is reviewed. Some results of Doppler tomography of emission lines are presented.

Structuring, Motions and Shapes of Corona Emission Line Profiles

1994 ◽  
Vol 144 ◽  
pp. 421-426
Author(s):  
N. F. Tyagun
Keyword(s):  
Emission Line ◽  
Filling Factor ◽  
Direct Relationship ◽  
Coronal Plasma ◽  
Line Of Sight ◽  
Line Profiles ◽  
The Difference ◽  
Yellow Line ◽  
Red Line

AbstractThe interrelationship of half-widths and intensities for the red, green and yellow lines is considered. This is a direct relationship for the green and yellow line and an inverse one for the red line. The difference in the relationships of half-widths and intensities for different lines appears to be due to substantially dissimilar structuring and to a set of line-of-sight motions in ”hot“ and ”cold“ corona regions.When diagnosing the coronal plasma, one cannot neglect the filling factor - each line has such a factor of its own.

Emission line profiles of AGNs and QSOs

1994 ◽  
Vol 222 (1-2) ◽  
pp. 91-106 ◽  
Author(s):  
D. Basu
Keyword(s):  
Emission Line ◽  
Line Profiles

scholarly journals Spectroscopy and Optical/IR Photometry of the Cataclysmic Variable CPD-48° 1577

1984 ◽  
Vol 80 ◽  
pp. 145-151
Author(s):  
W. Wargau ◽  
A. Bruch ◽  
H. Drechsel ◽  
J. Rahe ◽  
R. Schoembs
Keyword(s):  
Emission Line ◽  
Cataclysmic Variable ◽  
Line Profiles ◽  
Photometric Variability ◽  
Ir Photometry

AbstractThe photometric variability of CPD-48°1577 in the optical and IR ranges is discussed. The structure and variation of prominent emission line profiles are investigated. An estimate of the distance is given.

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 Hour-timescale profile variations in the broad Balmer lines of the Seyfert galaxy Hour-timescale profile variations in the broad Balmer lines of the Seyfert galaxy Markarian 6

2013 ◽  
Vol 9 (S304) ◽  
pp. 407-408
Author(s):  
Norayr S. Asatrian
Keyword(s):  
Fine Structure ◽  
Emission Line ◽  
Sampling Rate ◽  
Seyfert Galaxy ◽  
Special Astrophysical Observatory ◽  
Balmer Line ◽  
Line Profiles ◽  
Balmer Lines ◽  
Profile Changes ◽  
Hydrogen Emission Line

AbstractPart of results of the multi-epoch intranight optical spectroscopic monitoring of the Markarian 6 nucleus carried out at the telescopes of 6-m of the Special Astrophysical Observatory (Russia), 2.6-m of the Byurakan Astrophysical Observatory (Armenia) and 2-m of the Tautenburg Observatory (Germany) is presented.Observations were made in 1979, 1986, 1988-1991 and 2007-2009 during a total of 33 nights with an average sampling rate of 4 spectra per night. TV-scanner and long-slit spectrographs equipped with Image Tube and CCD detector arrays were used. Altogether we analyzed 110 Hβ and 58 Hα region spectra to search for intranight variability in the broad hydrogen emission line profiles. The typical spectral resolutions were 4 Å for scanner spectra, 6 Å for photographic spectra, and 5 Å and 10 Å for CCD spectra. The S/N ratio at the continuum level near the Hβ and Hα lines was in the range 15–50.The purpose of the search was to look for the characteristic variability signatures of different kinematical models of the broad emission-line region. We considered the centering and guiding errors which can result in differences between spectra.We found variations in the broad Balmer line difference profiles on time scale of hour with the level of significance of 3.6 σ to 5.0 σ. Variations take the form of narrow, small bumps located at the blue and red sides or only at the blue side of the lines. In the intermediate level of broad line flux, the Hβ and Hα profiles show fine structure. Detected profile changes occurred at the same radial velocity shifts as the details in the fine structure.The variability is at least 2 orders of magnitude more rapid than any observed for broad Balmer line profiles in AGNs that we are aware of in the literature.Discovered extremely rapid line-profile variability may be associated with reverberation effects. Two-sided profile changes may indicate the response of circularly rotating hydrogen clouds in the BLR to a light pulse from a central source. One-sided profile variations may be attributed to a response of a non-disk component: the subarcsec scale region of the jet.

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