Gas shell target for laser initiation of thermonuclear reactions

A new approach is proposed for obtaining laser initiated thermonuclear burning of a shell target. Optical breakdown is induced in a deuterium-tritium mixture gas such that the spherical shock wave propagating from the breakdown center forms a relatively cold plasma shell with relative thickness about 10%. This shell is irradiated symmetrically by a series of laser pulses, leading to shell collapse. Calculations were made of the distribution of density and ion temperature at various instants of time as the sphere collapses under the action of three laser pulses. A simplified gasdynamic calculation gives an expression for the energies of successive pulses. The example considered resulted in a neutron yield of 1 billion neutrons, though better results can be obtained when the pulse is programmed.