'Flash' model as a possible explanation of the superluminal expansion velocities of components of extragalactic radio sources
Abstract
A model for the apparent superluminal expansion of components of extragalactic compact radio sources is described in which a radio outburst from a compact structure surrounded by a flattened, less dense cloud of strongly magnetized plasma is accompanied by an outward-propagating shock wave. The passage of the shock wave from the compact structure to the toroidal plasma cloud increases the ultrarelativistic electron flux, causing a simultaneous brightening of the entire surface of the cloud. Signals from different points on the cloud do not reach an observer simultaneously, so that the observer sees two flashes of light propagating to both sides of the cloud from the point nearest him. It is shown that the apparent expansion velocity will be superluminal for specific viewing conditions.
- Publication:
-
Astrofizicheskie Issledovaniia Izvestiya Spetsial'noj Astrofizicheskoj Observatorii
- Pub Date:
- 1980
- Bibcode:
- 1980AISAO..12...64G
- Keywords:
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- Astronomical Models;
- Extragalactic Radio Sources;
- Radio Interferometers;
- Very Long Base Interferometry;
- Flash;
- Light Transmission;
- Relativistic Electron Beams;
- Shock Wave Propagation;
- Toroidal Plasmas;
- Astrophysics