scholarly journals Emission-Line Asymmetries and the Kinematics of the Narrow-Line Region in AGNs

1989 ◽  
Vol 134 ◽  
pp. 347-348
Author(s):  
Richard A. Shaw ◽  
Michael M. De Robertis
Keyword(s):  
Emission Line ◽  
Fundamental Problem ◽  
Signal To Noise Ratio ◽  
Critical Density ◽  
High Signal ◽  
Symmetric Model ◽  
Narrow Line ◽  
Line Region ◽  
Wide Range ◽  
Narrow Line Region

We have obtained high signal-to-noise ratio CCD spectra at ≤ 150 km/s resolution for 6 high-ionization Seyfert galaxies. We analyzed the profiles of the emission-lines over a wide range in both ionization potential (IP) and critical density (Ncr) in order to study the fundamental problem of cloud motion in the narrow-line region (NLR). Using the known correlations between FWHM and IP and/or Ncr for these galaxies, and assuming that the blueward profile asymmetries result from the combined effects of radially infalling or outflowing clouds and extinction within or between them, we deconvolve these effects by analyzing the correlation between emission-line asymmetries and both IP and Ncr. We find fair to good correlations in the sense that lines with high IP and Ncr also tend to have high asymmetry, while lines with low IP and Ncr have low but usually non-zero asymmetry. Simulated emission-line profiles generated with a spherically-symmetric model of a NLR suggest that the extinction arises primarily within radially infalling clouds.

scholarly journals Emission-line profiles and kinematics of the narrow-line region in Seyfert and radio galaxies

1981 ◽  
Vol 247 ◽  
pp. 403 ◽  
Author(s):  
T. M. Heckman ◽  
H. R. Butcher ◽  
G. K. Miley ◽  
W. J. M. van Breugel
Keyword(s):  
Emission Line ◽  
Radio Galaxies ◽  
Narrow Line ◽  
Line Profiles ◽  
Line Region ◽  
Narrow Line Region

scholarly journals Narrow Line Region in NGC 4151 Nucleus

1989 ◽  
Vol 134 ◽  
pp. 296-297
Author(s):  
V. I. Pronik
Keyword(s):  
Ionization Potential ◽  
Critical Density ◽  
List Type ◽  
Type Number ◽  
Narrow Line ◽  
Gas Velocity ◽  
Degree Of Ionization ◽  
Ngc 4151 ◽  
Line Region ◽  
Narrow Line Region

The well-known correlations of forbidden lines FWHM with the critical density for collisional de-excitation and with the ionization potential mean, that: i.the noticeable part of forbidden lines emission must arise in a gas of a rather high density n ∼ ncii.the gas velocity, the density and the degree of ionization they all increase toward the centre of the nucleus.

Space Telescope Imaging Spectrograph Long‐Slit Spectroscopy of the Narrow‐Line Region of NGC 4151. I. Kinematics and Emission‐Line Ratios

2000 ◽  
Vol 531 (1) ◽  
pp. 257-277 ◽  
Author(s):  
C. H. Nelson ◽  
D. Weistrop ◽  
J. B. Hutchings ◽  
D. M. Crenshaw ◽  
T. R. Gull ◽  
...  
Keyword(s):  
Emission Line ◽  
Narrow Line ◽  
Space Telescope ◽  
Ngc 4151 ◽  
Line Region ◽  
Narrow Line Region ◽  
Imaging Spectrograph

scholarly journals Photoionization, line emission diagnostics

2013 ◽  
Vol 9 (S304) ◽  
pp. 18-18
Author(s):  
Lisa Kewley
Keyword(s):  
Emission Line ◽  
Radiation Field ◽  
Line Emission ◽  
Narrow Line ◽  
Ionization State ◽  
Integral Field Spectroscopy ◽  
Field Spectroscopy ◽  
Line Region ◽  
Narrow Line Region ◽  
Integral Field

AbstractPhotoionization models for AGN, including Seyfert and LINERs are discussed. These photoionization models can be used to derive emission-line diagnostics for AGN that can determine the properties of the AGN and surrounding ISM, including the relative AGN contribution to the EUV radiation field, the hardness of the AGN radiation field, the ionization state of the gas, and the metallicity of the narrow-line region. It is shown how the AGN emission-line diagnostics are expected to change with redshift. Finally, latest application of these models by the author to wide integral field spectroscopy to separate starburst and AGN contributions in composite galaxies are presented.

scholarly journals Cospatial Line Emission and Accelerated Outflow in the Spatially Resolved Narrow-Line Region of NGC 4151: Confirming Model Predictions

1997 ◽  
Vol 159 ◽  
pp. 359-360
Author(s):  
D. Moore ◽  
R.D. Cohen ◽  
M.M. De Robertis
Keyword(s):  
Emission Line ◽  
Spectral Resolution ◽  
Line Emission ◽  
Narrow Line ◽  
Line Flux ◽  
Ngc 4151 ◽  
Spatially Resolved ◽  
Line Region ◽  
Model Predictions ◽  
Narrow Line Region

AbstractWe present results of high S/N, high spatial and spectral resolution (0″.65 and 0.8Å FWHM, respectively) spectrophotometry of the NLR of NGC 4151 using the Keck 10-m Telescope. The observations are the first in a series that test unambiguously several specific predictions that are based on earlier modeling of spatially unresolved emissionline spectra. Importantly, we partially resolve the source of most of the emission-line flux. Thus, the observations suitably complement analyses of spatially unresolved NLR spectra.

scholarly journals Substructures in the Narrow-Line Region of AGN

1989 ◽  
Vol 134 ◽  
pp. 312-313
Author(s):  
Sylvain Veilleux
Keyword(s):  
High Resolution ◽  
Emission Line ◽  
Seyfert Galaxies ◽  
Narrow Line ◽  
Line Profiles ◽  
Preliminary Results ◽  
Line Region ◽  
Narrow Line Region ◽  
Narrow Emission ◽  
Resolution Study

The preliminary results of a high-resolution study of narrow emission-line profiles in bright Seyfert galaxies are reported. Profile substructures such as secondary peaks and shoulders are observed in nearly all the objects. The results of profile comparisons in Mrk 359, Mrk 533, and Mrk 1066 are briefly discussed.

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