Angular size-flux density relation for extragalactic radio sources.
Abstract
A comparison has been made of the maximum angular extents of 163 weak extragalactic radio sources observed by the method of lunar occultation at Ootacamund with those for 199 strong sources from the 3CR complete sample. The angular sizes of the 6z sources with flux densities S405 i6 Jy (i Jy = io-26 W rn-2 Hz-') in the All-sky catalogue of Robertson were also considered. Over a flux density range of about 0.3-100 Jy at 408 MHz, it is found that the median value of angular size Orn increases with flux density S and is related approximately as 0m oc S 1/2 A similar relation is found if the identified QSOs are excluded from the source samples. These results indicate that statistically the weaker sources are located farther away. Since both 0 and S are dependent on world models, their relationship is of value for cosmological investigations.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 1975
- DOI:
- 10.1093/mnras/172.3.501
- Bibcode:
- 1975MNRAS.172..501S
- Keywords:
-
- Data Correlation;
- Extragalactic Radio Sources;
- Lunar Occultation;
- Quasars;
- Radiant Flux Density;
- Size Determination;
- Histograms;
- Radio Astronomy;
- Radio Galaxies;
- Red Shift;
- Astrophysics