What Is the Difference between Radio-loud and Radio-quiet Objects?
Abstract
Direct images have been obtained with the Canada-France-Hawaii Telescope of a sample of low-redshift, high-luminosity, radio-quiet QSOs, whose redshift and luminosity distribution matches that of a radio-loud sample previously discussed. We present measures of the nuclear and host galaxy luminosities and colors, and a morphological discussion of the host galaxies. We compare five samples of radio-loud and radio-quiet QSOs from the same telescope which enable us to compare the effects of radio activity, redshift, nuclear luminosity, and detector quality on these properties. We find that radio-quiet QSOs reside in galaxies which are smaller, fainter, and redder than the host galaxies of radio-loud QSOs. These properties are generally consistent with the suggestion that radio-quiet QSOs live in spiral-type galaxies and radio-loud QSOs live in more elliptical-type galaxies. We find significantly less evidence for tidal interactions among the radio-quiet objects, although they appear to live in somewhat richer environments in terms of nearby companions. We present a general discussion of QSO host galaxy properties and puzzles.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1989
- DOI:
- 10.1086/167626
- Bibcode:
- 1989ApJ...342..660H
- Keywords:
-
- Astronomical Photometry;
- Luminosity;
- Quasars;
- Radio Astronomy;
- Radio Emission;
- Galactic Nuclei;
- Galactic Structure;
- Interacting Galaxies;
- Radio Galaxies;
- Red Shift;
- Astrophysics;
- GALAXIES: INTERACTIONS;
- GALAXIES: PHOTOMETRY;
- GALAXIES: STRUCTURE;
- QUASARS;
- RADIO SOURCES: GALAXIES