Home     Getting Started     To Survive in the Universe    
Inhabited Sky
    News@Sky     Astro Photo     The Collection     Forum     Blog New!     FAQ     Press     Login  

HD 179504


Contents

Images

Upload your image

DSS Images   Other Images


Related articles

The emission spectrum of active galactic nuclei. II - High column density photoionization models and low ionization lines
Current one-component models of the broad line region of quasars fail toexplain the strength of low ionization lines. A two-componentphotoionization model where the high and low ionization lines areallowed to arise from different kinds of clouds is explored. A spectraldistribution of the incident radiation which tends to overestimate theX-ray flux around 3 keV is adopted in order to enhance the extent andthe heating of the excited H I region. After discussing the influence ofseveral parameters, it is concluded that the model is still unable toexplain the observed ratio Fe II/H? and that another kind of cloud,presumably not heated by photoionization, is needed to emit Fe II.

Submit a new article


Related links

  • - No Links Found -
Submit a new link


Member of following groups:


Observation and Astrometry data

Constellation:Τηλεσκόπιον
Right ascension:19h15m43.94s
Declination:-53°51'42.2"
Apparent magnitude:8.91
Distance:117.925 parsecs
Proper motion RA:30.8
Proper motion Dec:-96.1
B-T magnitude:9.4
V-T magnitude:8.951

Catalogs and designations:
Proper Names   (Edit)
HD 1989HD 179504
TYCHO-2 2000TYC 8760-802-1
USNO-A2.0USNO-A2 0300-35546305
HIPHIP 94660

→ Request more catalogs and designations from VizieR