Optical Inverse Compton Emission in Extragalactic Radio Sources

Abstract

In this contribution the reported detection by Saslaw, Tyson and Crane (1978) of weak optical emission in the lobes of three 3C sources — 3C 265, 3C 285 and 3C 390.3 — is reappraised in the framework of three optical emission mechanisms — synchrotron (SYN), synchrotron inverse Compton (SIC) and blackbody inverse Compton (BIC). This effort has been motivated partly by the knowledge that the contribution to the synchrotron inverse Compton emission in a radio source component is likely to become significant for very compact and bright radio components (see e.g. Okoye 1972), and partly by the recent availability of high resolution radio frequency structural data on the sources in question. Another incentive arose from the demands of a separate investigation into high energy particles interactions in radio sources (reported by Okoye and Okeke in this volume) involving very high energy protons thus making it necessary to ascertain whether such highly energetic particles exist in radio source components.