Present status and future prospect of Fast Ignition Realization Experiment (FIREX) Project at ILE, Osaka

Thermonuclear ignition and subsequent burn are key physics for achieving laser fusion. In fast ignition, a highly compressed fusion fuel generated with multiple ns‐laser beams is rapidly heated with a large energy, ps‐laser pulse in prior to core disassembly. This scheme has a high potential to achieve ignition and burn since driver energy required for high fusion gain is predicted to be about one tenth of that needed for the central ignition scheme. In Japan, Fast Ignition Realization Experiment (FIREX) project has been started to clarify the physics of energy transport and deposition in the core plasma and to demonstrate fuel temperature of above 5 keV. After the success, FIREX‐I will be followed by the second phase of the project (FIREX‐II) to demonstrate ignition and burn. LFEX laser, designed to deliver a laser pulse of 10 kJ in 10 ps, are operational and the first phase of FIREX experiments has been stated. A new target is proposed to attain dense compression of fuel and improve laser‐core coupling efficiency by adopting double‐cone structure, a low‐density inner liner, low‐Z outer coating, and Br‐doped fuel shell. In this paper, present status and near term prospects of the FIREX‐I project will be reported together with activities on target designing, laser development, and plasma diagnostics.