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.

scholarly journals NEON AND $[{\rm{C}}\,{\rm{II}}]$ 158 μ m EMISSION LINE PROFILES IN DUSTY STARBURSTS AND ACTIVE GALACTIC NUCLEI

2016 ◽  
Vol 226 (1) ◽  
pp. 11 ◽  
Author(s):  
Anahit Samsonyan ◽  
Daniel Weedman ◽  
Vianney Lebouteiller ◽  
Donald Barry ◽  
Lusine Sargsyan
Keyword(s):  
Emission Line ◽  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Line Profiles

scholarly journals Radiative-transfer modelling of funnel flows

2007 ◽  
Vol 3 (S243) ◽  
pp. 83-94
Author(s):  
Tim J. Harries
Keyword(s):  
Numerical Methods ◽  
Radiative Transfer ◽  
Emission Line ◽  
Main Sequence ◽  
Line Profiles ◽  
Stellar Radius ◽  
Transfer Modelling ◽  
Synthetic Line ◽  
Made In ◽  
Geometry And Kinematics

AbstractEmission line profiles from pre-main-sequence objects accreting via magnetically-controlled funnel flows encode information on the geometry and kinematics of the material on stellar radius scales. In order to extract this information it is necessary to perform radiative-transfer modelling of the gas to produce synthetic line profiles. In this review I discuss the physics that needs to be included in such models, and the numerical methods and assumptions that are used to render the problem tractable. I review the progress made in the field over the last decade, and summarize the main successes and failures of the modelling work.

scholarly journals The veiling spectrum of DI Cephei and its relationship to emission line profiles

2005 ◽  
Vol 445 (1) ◽  
pp. 323-329 ◽  
Author(s):  
J. F. Gameiro ◽  
D. F. M. Folha ◽  
P. P. Petrov
Keyword(s):  
Emission Line ◽  
Line Profiles

scholarly journals Spatial and temporal variations of K Ca II line profile shapes in different structures of the solar chromosphere. I. Features of individual profiles

2018 ◽  
Vol 4 (4) ◽  
pp. 3-13
Author(s):  
Ирина Турова ◽  
Irina Turova ◽  
София Григорьева ◽  
Sofiya Grigoryeva ◽  
Ольга Ожогина ◽  
...  
Keyword(s):  
Temporal Variations ◽  
Disk Center ◽  
Spatial And Temporal Variations ◽  
Solar Chromosphere ◽  
Line Profiles ◽  
Thermodynamic Conditions ◽  
Characteristic Points ◽  
Scatter Plots ◽  
The Difference ◽  
Individual Profiles

We have studied Ca II K line profiles, using two time series of spectrograms taken in two regions near the solar disk center. In each of the regions, the spectrograph slit cut out several areas of the quiet region and a plage. For the selected chromospheric structures, we have derived K line profiles and have defined a number of parameters that characterize the spatial and temporal variations of the profiles. The analysis of profile shapes in different structures belonging to the same moment of time has shown that there are structures whose profiles differ only slightly from each other in the photosphere, but differ dramatically in the chromosphere. The structures begin to differ from the level of formation of K1 and continue to differ further in the chromosphere. There are, however, structures which begin to differ at the level of the photosphere and continue to differ in the chromosphere. The difference between profile shapes in different structures is likely to be associated both with different thermodynamic conditions and with different magnetic field topology at a given point at a given time. We have examined temporal variations of the K Ca II line profiles in structural chromospheric elements, which are caused by the process of K2v-grains. In most of the studied areas of the chromospheric structures, the brightening of the K2v peak develops according to the “common” scenario: at the time of maximum bright-ness, the line shifts toward the red side. There are, however, cases when the brightening of the K2v peak occurs with a shift of the line to the violet side or with no shift at all. We have constructed scatter plots for some pairs of profile parameters related to intensities at characteristic points of the profile and their shifts. A correlation has been found between intensities in the center and wings of the K line. The correlation between shifts of the K2v and K2r peaks is very weak or completely absent.

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