scholarly journals [ITAL]Hubble Space Telescope[/ITAL] STIS Observations of the Kinematics of Emission-Line Nebulae in Three Compact Steep-Spectrum Radio Sources

2002 ◽  
Vol 123 (5) ◽  
pp. 2333-2351 ◽  
Author(s):  
Christopher P. O’Dea ◽  
Willem H. de Vries ◽  
Anton M. Koekemoer ◽  
Stefi A. Baum ◽  
Raffaella Morganti ◽  
...  
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Radio Sources ◽  
Space Telescope ◽  
Spectrum Radio

Hubble Space Telescope Imaging of Compact Steep Spectrum Radio Sources

1997 ◽  
Vol 110 (2) ◽  
pp. 191-211 ◽  
Author(s):  
W. H. de Vries ◽  
C. P. O'Dea ◽  
S. A. Baum ◽  
W. B. Sparks ◽  
J. Biretta ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Radio Sources ◽  
Space Telescope ◽  
Spectrum Radio

scholarly journals Jet–Cloud Interactions in Compact Steep Spectrum Radio Sources

2003 ◽  
Vol 20 (1) ◽  
pp. 88-93 ◽  
Author(s):  
C. P. O'Dea ◽  
W. H. de Vries ◽  
A. M. Koekemoer ◽  
S. A. Baum ◽  
D. J. Axon ◽  
...  
Keyword(s):  
Emission Line ◽  
Radio Source ◽  
Bow Shock ◽  
Radio Sources ◽  
Line Profiles ◽  
Multiple Components ◽  
Spectrum Radio ◽  
Velocity Variations

AbstractWe have obtained HST/STIS long slit spectroscopy of the aligned emission line nebulae in three compact steep spectrum (CSS) radio sources — 3C 67, 3C 277.1, and 3C 303.1. We find systematic offsets (˜300–500 kms) of the emission line velocities on one or both sides of the radio sources. We also see evidence for broad lines (FWHM ˜500 kms) and complex emission line profiles. In 3C 303.1 the data are consistent with multiple components and possibly split lines. The amplitude of the velocity variations is not so large as to exclude gravitationally-induced motions. However, the complex kinematics, the lack of a signature of Keplerian rotation, and the association of the velocity variations with the radio lobes are consistent with the observed ˜300–500 kms velocities being driven by the expansion of the radio source. Acceleration of the clouds by the bow shock is plausible given the estimated densities in the clouds and the velocities observed in the much smaller compact symmetric objects and with expansion velocities estimated from spectral ageing. This conclusion is unchanged if we consider the scenario in which the cloud acceleration is dominated by the post bow shock flow.

Hubble Space Telescope Ultraviolet Spectrum of ARP 102B, the Prototypical Double-peaked Emission-Line AGN

1996 ◽  
Vol 464 ◽  
pp. 704 ◽  
Author(s):  
Jules P. Halpern ◽  
Michael Eracleous ◽  
Alexei V. Filippenko ◽  
Kaiyou Chen
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Ultraviolet Spectrum ◽  
Space Telescope

Emission Line Properties of Active Galactic Nuclei from a Post‐COSTAR Hubble Space Telescope Faint Object Spectrograph Spectral Atlas

2004 ◽  
Vol 150 (1) ◽  
pp. 165-180 ◽  
Author(s):  
Joanna K. Kuraszkiewicz ◽  
Paul J. Green ◽  
D. Michael Crenshaw ◽  
Jay Dunn ◽  
Karl Forster ◽  
...  
Keyword(s):  
Emission Line ◽  
Active Galactic Nuclei ◽  
Hubble Space Telescope ◽  
Galactic Nuclei ◽  
Space Telescope ◽  
Faint Object ◽  
Faint Object Spectrograph

scholarly journals THE 3D-HST SURVEY: HUBBLE SPACE TELESCOPE WFC3/G141 GRISM SPECTRA, REDSHIFTS, AND EMISSION LINE MEASUREMENTS FOR ∼100,000 GALAXIES

2016 ◽  
Vol 225 (2) ◽  
pp. 27 ◽  
Author(s):  
Ivelina G. Momcheva ◽  
Gabriel B. Brammer ◽  
Pieter G. van Dokkum ◽  
Rosalind E. Skelton ◽  
Katherine E. Whitaker ◽  
...  
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Space Telescope

scholarly journals The dynamics of the broad-line region in NGC 3227

2020 ◽  
Vol 500 (1) ◽  
pp. 786-794
Author(s):  
Nick Devereux
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Outer Radius ◽  
Short Time Scale ◽  
Broad Line ◽  
Fall Velocity ◽  
Space Telescope ◽  
X Ray ◽  
Broad Line Region ◽  
Line Region

ABSTRACT Archival Hubble Space Telescope (HST) observations of the Seyfert 1 nucleus of NGC 3227 obtained with the Space Telescope Imaging Spectrograph (STIS) are re-examined in order to constrain a viable photoionization model for the broad-line region (BLR). The results imply that the BLR is a partially ionized, dust-free, spherical shell that is collapsing, supersonically, at the free-fall velocity due to its proximity to a supermassive black hole. The BLR is ionization bounded at the outer radius, coincident with the dust reverberation radius, and transforms into an X-ray emitting plasma inside the Balmer reverberation radius as the central UV–X-ray source is approached. Only 40 M⊙ of Hydrogen are required to explain the Balmer emission-line luminosity, but it is compressed by gravity into a column measuring 5.5 × 1024 atoms cm−2. Assuming radiatively inefficient accretion, the X-ray luminosity requires ∼10−2 M⊙ yr−1. However, the mass inflow rate required to explain the luminosity of the broad H α emission line is ∼1 M⊙ yr−1. The very large disparity between these two estimates indicates that 99 per cent of the inflowing gas must be re-directed into an outflow, and on a very short time-scale corresponding to ∼40 yr. Alternatively, the radiative efficiency of the inflow has been overestimated, or the X-ray luminosity has been underestimated, a distinct possibility if the BLR is indeed Compton-thick.

scholarly journals Imaging and spectroscopy of Magellanic Cloud Planetary Nebulae obtained with the Hubble Space Telescope

1997 ◽  
Vol 180 ◽  
pp. 477-477
Author(s):  
E. Vassiliadis ◽  
M. Dopita ◽  
R. C. Bohlin ◽  
J. P. Harrington ◽  
S. J. Meatheringham ◽  
...  
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Planetary Nebulae ◽  
Magellanic Cloud ◽  
Magellanic Clouds ◽  
Space Telescope ◽  
Imaging And Spectroscopy

The majority of planetary nebulae (PNe) at the distance of the Magellanic Clouds typically subtend 1 arcsec or less on the sky. The Planetary Camera onboard the Hubble Space Telescope has a scale of 0.044 arcsec per pixel and is therefore ideal to use to image these objects. At present, 16 LMC and 5 SMC objects have been imaged in the [O III] 5007 angstrom emission line, as part of this program. An additional 10 LMC and 5 SMC objects have been imaged in the same line under the Guaranteed Time Observer program.

Emission Line Properties of Active Galactic Nuclei from a Pre‐COSTAR Faint Object Spectrograph Hubble Space Telescope Spectral Atlas

2002 ◽  
Vol 143 (2) ◽  
pp. 257-276 ◽  
Author(s):  
Joanna K. Kuraszkiewicz ◽  
Paul J. Green ◽  
Karl Forster ◽  
Thomas L. Aldcroft ◽  
Ian N. Evans ◽  
...  
Keyword(s):  
Emission Line ◽  
Active Galactic Nuclei ◽  
Hubble Space Telescope ◽  
Galactic Nuclei ◽  
Space Telescope ◽  
Faint Object ◽  
Faint Object Spectrograph

scholarly journals TheChandra,Hubble Space Telescope, and VLA View of the Circumnuclear Extended Emission in the Narrow Emission Line Galaxy NGC 2110

2006 ◽  
Vol 653 (2) ◽  
pp. 1121-1128 ◽  
Author(s):  
Daniel A. Evans ◽  
Julia C. Lee ◽  
Maria Kamenetska ◽  
Sarah C. Gallagher ◽  
Ralph P. Kraft ◽  
...  
Keyword(s):  
Emission Line ◽  
Hubble Space Telescope ◽  
Space Telescope ◽  
Line Galaxy ◽  
Extended Emission ◽  
Narrow Emission
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