Hotspots in radio galaxies : a comparison with hydrodynamic simulations.
Abstract
Surface brightness distributions are derived for the beam cap of an axisymmetric supersonic jet ramming through its confining medium. The detailed structure and time-evolution of the working surface is computed numerically with a high-resolution gas dynamics code employing a special technique for accurately tracking and preserving the jet boundary. The synchrotron emissivity is assumed to be proportional to the square of the gas pressure inside the jet, and zero outside. The geometry of the beam cap is found to change on a dynamical time-scale, producing an enormous variety of hotspot shapes in a single evolution. A classification of well-resolved hotspots in radio galaxies is made with which the derived contour maps are compared. Several quite common features of observed hotspots are reproduced.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 1985
- DOI:
- 10.1093/mnras/214.2.67
- Bibcode:
- 1985MNRAS.214...67S
- Keywords:
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- Brightness Distribution;
- Computational Astrophysics;
- Hydrodynamics;
- Plasma Jets;
- Radio Galaxies;
- Astronomical Maps;
- Galactic Nuclei;
- Surface Properties;
- Synchrotron Radiation;
- Astrophysics