NGC 5506: an X-ray Seyfert galaxy.
Abstract
A photographic red spectrum taken along the major axis of the dust-riddled X-ray galaxy NGC 5506 is presented. Both the permitted and the forbidden lines are found to have broad wings, with a total width in excess of 1500 km/s. It is noted that with the slit along the major axis, emission is detected out to a distance of 48 arcsec or 8.3 kpc (for H equals 50 km/s per Mpc). A mass of about 40 billion solar masses to a distance of 8.3 kpc is calculated for an infinitely thin disk; for the previously reported radius of 15.0 kpc, the mass is estimated as approximately 100 billion solar masses if the rotation curve remains flat between 8.3 and 15.0 kpc. It is concluded that NGC 5506 appears to be a normal Seyfert 2 galaxy and cannot properly be called a narrow-emission-line galaxy.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1978
- DOI:
- 10.1086/182758
- Bibcode:
- 1978ApJ...224L..55R
- Keywords:
-
- Astronomical Spectroscopy;
- Galactic Rotation;
- Seyfert Galaxies;
- X Ray Sources;
- Cosmic Dust;
- Emission Spectra;
- Line Spectra;
- Velocity Measurement;
- Astrophysics;
- Seyfert Galaxies:X Rays;
- Spectra:X-Ray Galaxies