Finken, K. H. (Corresponding author)FZJ* ; Institut für Plasmaphysik (Jülich) ; Association EURATOM - Forschungszentrum Jülich

1994
Forschungszentrum Juelich Juelich

Report No.: Juel-2980

Abstract: In thermonuclear fusion research, pellet plasma interaction occurs in two important areas: One is the so-called inertial confinement and the second one is the injection of pellets in a magnetically confined plasma. In inertial confinement, a spherical target of a few millimeters diameter filled with a deuterium-tritium mixture - the pellet - is bombarded with a well focussed high power beam of either photons (laser-beam, indirectly by laser beam initiated incoherent X-ray radiation) or particles (electron-, light ion- or heavy ion-beam). The beam energy has to be in the order of Mega-Joule for a time span of several nanoseconds. The beam heats the outer surface of the pellet and forms an expanding plasma cloud. The expansion establishes a reaction-force directed towards the pellet center and initiates a compression wave into the pellet. To reach a positive energy balance, i.e. to extract more fusion power from the pellet than has been put in by the beam, it is necessary to compress the pellet center to a density of over one thousand times the solid state density. Under this condition the inertia of the pellet matter keeps the material together long enough for obtaining the desired burning rate. Inertial confinement attracts much attention from the military side and, therefore, some aspects are still classified. In the following, inertial confinement will not be discussed.

Keyword(s): hot plasma ; interaction

1. Plasmaphysik (IEF-4)