Production of highly ionized plasma by microdot array irradiation and its application to compact x-ray lasers

Plasma production and expansion by the irradiation of an array of small spot have been investigated from a point of view of soft x-ray laser generation. The expansion nature of highly ionized ions produced by the micro-dot array irradiation method has ben measured and compared with that by the simple line irradiation. Spatial distribution of gain coefficient of the Li-like Al ion transition lines have also been measured. It has been clarified that rapid expansion and efficient cooling are achieved in plasmas produced by the micro-dot array irradiation method.