scholarly journals The Coronal Emission-Line Region in AGNs: A Hubble Space Telescope View

2009 ◽  
Vol 5 (S267) ◽  
pp. 122-122
Author(s):  
X. Mazzalay ◽  
A. Rodríguez-Ardila ◽  
S. Komossa
Keyword(s):  
Physical Properties ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Hubble Space Telescope ◽  
Seyfert Galaxies ◽  
Coronal Line ◽  
Coronal Emission ◽  
Line Region ◽  
High Ionization ◽  
Coronal Emission Line

AbstractWe present a study of HST/STIS optical spectra of a sample of ten Seyfert galaxies aimed at analyzing the structure and physical properties of the coronal line region. The high spatial resolution provided by STIS (about 7 pc for the closest objects) allowed us to resolve the coronal line region and obtain key information about the kinematics of the coronal-line gas, measure directly its spatial scale, and study the mechanisms that drive the high-ionization lines.

scholarly journals Properties of Warm Absorbers and Constraints from their Optical and UV Line Emission

1997 ◽  
Vol 159 ◽  
pp. 246-247
Author(s):  
Stefanie Komossa ◽  
Henner Fink
Keyword(s):  
Line Emission ◽  
Seyfert Galaxies ◽  
Coronal Line ◽  
X Ray ◽  
Line Region ◽  
High Ionization ◽  
Photon Index ◽  
Balmer Lines ◽  
The Individual ◽  
Ionization Parameter

We have studied the warm absorbers in several Seyfert galaxies using both PI and archival ROSAT data. The parameters that govern the emissivity of the ionized material, ionization parameter U, warm-absorber column density Nwa, and the source intrinsic power-law photon index Γx, are determined from X-ray spectral fits. These are then used to predict the expected IR to UV line emission of the ionized material in the individual objects. In particular, the possibility of a warm-absorber origin of one of the known emission-line regions in AGN is assessed. Good ‘candidate components’ are, e.g., the coronal-line region, and/or the high-ionization component of the NLR, or the component responsible for broad wings in the Balmer lines. All calculations have been carried out using the code CLOUDY (Ferland 1993).

scholarly journals High Spatial Resolution Mid-Infrared Observations of Three Seyfert Galaxies

2003 ◽  
Vol 126 (1) ◽  
pp. 143-152 ◽  
Author(s):  
B. T. Soifer ◽  
J. J. Bock ◽  
K. Marsh ◽  
G. Neugebauer ◽  
K. Matthews ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Seyfert Galaxies ◽  
Mid Infrared ◽  
Infrared Observations

scholarly journals High-Ionization Nuclear Emission-Line Region of Seyfert Galaxies

2000 ◽  
Vol 119 (6) ◽  
pp. 2605-2628 ◽  
Author(s):  
Tohru Nagao ◽  
Yoshiaki Taniguchi ◽  
Takashi Murayama
Keyword(s):  
Emission Line ◽  
Seyfert Galaxies ◽  
Line Region ◽  
High Ionization

scholarly journals Coronal-line forest active galactic nuclei – I. Physical properties of the emission-line regions

2020 ◽  
Vol 500 (2) ◽  
pp. 2666-2684
Author(s):  
F C Cerqueira-Campos ◽  
A Rodríguez-Ardila ◽  
R Riffel ◽  
M Marinello ◽  
A Prieto ◽  
...  
Keyword(s):  
Emission Line ◽  
Active Galactic Nuclei ◽  
Near Infrared ◽  
Galactic Nuclei ◽  
Infrared Emission ◽  
Ionization Mechanism ◽  
Coronal Line ◽  
Coronal Emission ◽  
High Ionization ◽  
Stellar Velocity

ABSTRACT Coronal-line forest (CLiF) active galactic nuclei (AGNs) are characterized by strong high-ionization lines, which contrasts with what is found in most AGNs. Here, we carry out a multiwavelength analysis aimed at understanding the physical processes in the narrow-line region (NLR) of these objects, and at discovering whether they are indeed a special class of AGNs. By comparing coronal emission-line ratios we conclude that there are no differences between CLiF and non-CLiF AGNs. We derive physical conditions of the NLR gas and we find electron densities in the range of 3.6 × 102 to 1.7 × 104 cm−3 and temperatures of 3.7 × 103 to 6.3 × 104 K, suggesting that the ionization mechanism is associated primarily with photoionization by the AGN. We suggest an NLR dominated by matter-bounded clouds to explain the high-ionization line spectrum observed. The mass of the central black hole, derived from the stellar velocity dispersion, shows that most of the objects have values in the interval 107–108 M⊙. Our results imply that CLiF AGNs are not in a separate category of AGNs. In all optical/near-infrared emission-line properties analysed, they represent an extension to the low/high ends of the distribution within the AGN class.

scholarly journals High Spatial Resolution Mid‐Infrared Observations of Five Seyfert Galaxies

2004 ◽  
Vol 116 (820) ◽  
pp. 493-496 ◽  
Author(s):  
B. T. Soifer ◽  
G. Neugebauer ◽  
K. Matthews ◽  
E. Egami ◽  
L. Armus
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Seyfert Galaxies ◽  
Mid Infrared ◽  
Infrared Observations

scholarly journals HST and KECK Observations of High Redshift Radio Galaxies

1996 ◽  
Vol 175 ◽  
pp. 577-580
Author(s):  
W.J.M. Van Breugel
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Hubble Space Telescope ◽  
High Redshift ◽  
Radio Galaxies ◽  
Space Telescope ◽  
Comprehensive Program ◽  
Resolution Imaging ◽  
High Spatial Resolution Imaging ◽  
Optical Telescopes

Together with several of my colleagues I have embarked on a comprehensive program to study the radio–aligned restframe UV structures in high redshift radio galaxies (HzRGs) using some of the world's premier optical telescopes: the Hubble Space Telescope for high spatial resolution imaging, and the Keck 10m telescope for high S/N spectropolarimetry. I will discuss some of our latest results from these observations which elucidate, and at the same time obscure, our evolving understanding of HzRGs.

scholarly journals The Origin of the Coronal Lines in Seyfert Galaxies

1989 ◽  
Vol 134 ◽  
pp. 320-320
Author(s):  
K. T. Korista ◽  
G. J. Ferland
Keyword(s):  
Interstellar Medium ◽  
Spiral Galaxy ◽  
Seyfert Galaxies ◽  
Low Density ◽  
Coronal Line ◽  
Model Calculations ◽  
Line Region ◽  
Seyfert Nucleus ◽  
Photoionization Model

Photoionization model calculations suggest the possibility that the coronal line region in Seyfert galaxies may be the result of an interstellar medium exposed to and subsequently photoionized by a “bare” Seyfert nucleus. A series of models are presented in which a “generic” AGN continuum illuminates the low-density phase of the ISM of a spiral galaxy (Korista and Ferland 1988).

scholarly journals Physical Conditions of the Coronal Line Region in Seyfert Galaxies

1997 ◽  
Vol 110 (2) ◽  
pp. 287-297 ◽  
Author(s):  
Jason W. Ferguson ◽  
Kirk T. Korista ◽  
Gary J. Ferland
Keyword(s):  
Seyfert Galaxies ◽  
Coronal Line ◽  
Physical Conditions ◽  
Line Region

High Spatial Resolution 2D Spectrography of ENLR in Seyfert Galaxies

1994 ◽  
Vol 159 ◽  
pp. 445-445
Author(s):  
E. Pecontal ◽  
P. Ferruit
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Seyfert Galaxies ◽  
Spectral Domain ◽  
Radio Sources ◽  
Spatial Dimensions ◽  
Integral Field Spectrograph ◽  
Integral Field

Three active nuclei environments have been observed with the integral field spectrograph TIGER operating in the visible domain : Mkn 34, NGC 5929 and M 51. These three objects exhibit linear radio-sources evocating expulsion of plasmons from the nucleus. Long-slit or Pérot-Fabry observations showed that the gas of the galaxies is interacting with the radio-emitter, and models of this interaction have been proposed. These new observations combines the two spatial dimensions of integral field spectrography (with 0.7″ FWHM) with the rather large spectral domain of classical spectrography.

Sign in / Sign up

Export Citation Format

Share Document