Robustness of Key Parameters in Implosion of Multilayer Fuel Targets Against Change in Heavy-Ion Beam Parameters for Heavy-Ion Inertial Fusion

抄録

This study investigated the effects of heavy-ion beam (HIB) pulse waveform and irradiation time on the implosion process of a multilayer fuel target designed for heavy-ion inertial fusion (HIF). Achieving high beam intensity, beam quality, and precise timing synchronization is challenging owing to the space charge effect. Multilayer fuel targets with low-density foam layers may alleviate these beam condition requirements and help achieve robust, uniform implosion. Using a 1-D spherical coordinate hydrodynamic model, this study evaluated implosion dynamics and variation using the coefficient of variation. Results showed that multilayer targets offer enhanced robustness against beam irradiation time variations compared to conventional designs. The Pb pusher configuration consistently demonstrated superior stability, attributed to the high density and atomic number of Lead that influences transport and hydrodynamics. The foam layer also plays a crucial role in mitigating the adverse effects of timing fluctuations. These findings suggest that multilayer fuel targets, particularly with a Pb pusher, provide a compelling advantage for practical applications by offering improved robustness and simplifying parameter optimization procedures compared to conventional HIF targets.