Generation of Auroral Kilometric Radiation in Bounded Source Regions

Owing to the complete and precise wave/particle measurements performed by the Viking and FAST spacecraft in the sources of the terrestrial Auroral Kilometric Radiation, the conditions of generation of this coherent radio emission are now well documented. It has been demonstrated that the production of radio waves occurs in thin laminar regions that exactly correspond to the regions of auroral particle acceleration. We present and discuss observations, mainly performed by Viking, that have led to the conception of a model of wave generation by finite geometry sources.- The corresponding theoretical analysis is also presented. This model has certainly a very broad domain of applications, including radio emissions from other planets, from the Sun and more distant astrophysical objects.