The environments of FRII radio sources |
| |
| Authors: | M J Hardcastle D M Worrall |
| |
| Institution: | Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL |
| |
| Abstract: | Using ROSAT observations, we estimate gas pressures in the X-ray-emitting medium surrounding 63 FRII radio galaxies and quasars. We compare these pressures with the internal pressures of the radio-emitting plasma estimated by assuming minimum energy or equipartition. In the majority of cases (including 12/13 sources with modelled, spatially resolved X-ray emission) radio sources appear to be underpressured with respect to the external medium, suggesting that simple minimum-energy arguments underestimate the internal energy density of the sources. We discuss possible departures from the minimum-energy condition and the consequences of our result for models of the dynamics of radio galaxies, in particular self-similar models . |
| |
| Keywords: | galaxies: active galaxies: clusters: general X-rays: galaxies |
|
|
