Radio Galaxy Spectra

Abstract

Radio spectra of radio galaxies are often ascribed a simple power law form ($S_{\nu }\propto {\nu }^{\alpha }$) with the spectral index, $\alpha$, being of order -0.7. However, all radio galaxies deviate from this simple power law behaviour. In this paper we derive simple expressions for the average rest-frame spectra of FRI and FRII radio galaxies. These will be used to describe the spectral curvature of the parent (FRI and FRII) populations in models of radio source evolution.

4 pages, 3 figures, submitted to 'Particles & Fields in Radio Galaxies' eds Laing & Blundell, ASP conference series