VLBI obvservations of the double quasar 0957+561.
Abstract
VLBI observations of the double quasar 0957 + 561 at a wavelength of 6 cm are presented. Both the A and B sources were detected on an intercontinental baseline with peak cross-correlated flux densities of 26 + or - 5 and 20 + or - 5 mJy, respectively. This implies peak fringe visibilities of 0.7 + or - 0.2 for both sources. The simplest interpretation of the data is that both sources are about 1 milli-arcsec in diameter. Only a single peak is observed in the fringe-rate spectrum for each source. Hence, the data are inconsistent with a model of a double structure for either source in which the components have a flux density ratio of less than about 1.5 and a separation of greater than 20 milli-arcsec.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1981
- DOI:
- 10.1086/183442
- Bibcode:
- 1981ApJ...243L..57H
- Keywords:
-
- Gravitational Lenses;
- Quasars;
- Very Long Base Interferometry;
- Gravitational Effects;
- Radiant Flux Density;
- Radio Astronomy;
- Astronomy