SYMMETRIZING EFFECT OF AN X-RAY PREPULSE IN LASER TARGET COMPRESSION

Two-dimensional numerical calculations were made in a study of the sym metrising effect of an x-ray prepulse on the inhomogeneity of laser ta rget compression, It is suggested that a two-stage target, with its ou ter stage formed by a thin metal layer, can be used to generate such a prepulse, Correct selection of the parameters of this layer and of a laser prepulse can ensure symmetrisation of the inner working target w ith minimal undesirable preheating of the fuel, Such a target is accel erated and compressed at the expense of the energy of the main laser p ulse. The influence of a large-scale asymmetry of irradiation, associa ted with a specific geometry of the radiation reaching the target, may be reduced by a suitable variation of the shell thickness.