Experiment study of discharge characteristics and pumping efficiency of air bubble flash lamp

The improvement of the amplifier gain and amplifier efficiency is quite attractive in inertia confined fusion (ICF). As an important component of the amplifier, the flash lamp pumping efficiency directly affects the amplifier efficiency. In this paper, a new structure of flash lamp is designed and constructed, going for a higher pumping efficiency. Comparison between the new and the traditional structures are made, in terms of electrical characteristics, radiation and fluorescence behaviors of Nd: glass. Experimental results indicate that the resistance increases in the new structure, corresponding to a lower current and energy feeding. As a result, the intensities of radiation and fluorescence are improved by 3%~4% and 2%~3% respectively. The mechanisms of the improvement, the evolution of the discharge plasma channel, and the scheme of further optimization for the new structure are discussed.