Radio emission from radio-quiet quasars
Abstract
In a search for radio emission from bright, optically selected quasars, we detected ~50% of the quasars at 5 GHz. This radio detection rate is so much higher than that for faint quasars (<10%)1-4, that it requires that the distribution of radio(R)-to-optical(O) luminosity ratios (LR/LO) be correlated with optical properties and/or with distance (or cosmic epoch). The values of LR/LO in our sample range from ~10-2 to <10-5 (where radio detection is no longer possible). So broad and smooth a distribution argues against a distinct dichotomy between `radio-quiet' and `radio-loud' quasars. The quasars in our sample which remain undetected at radio frequencies must exhibit a spectral-flux distribution rising from the radio to optical, previously considered an `abnormal' spectrum for a quasar.
- Publication:
-
Nature
- Pub Date:
- January 1980
- DOI:
- 10.1038/283357a0
- Bibcode:
- 1980Natur.283..357C
- Keywords:
-
- Extraterrestrial Radio Waves;
- Quasars;
- Star Distribution;
- Stellar Luminosity;
- Radio Astronomy;
- Spectrum Analysis;
- Astrophysics