FIREX Project and Effects of Self‐generated Electric and Magnetic Fields on Electron Driven Fast Ignition

The fast ignition is a new scheme in laser fusion, in which higher energy gain is expected with smaller laser pulse energy. The cone target has been introduced for realizing higher coupling efficiency. At ILE, Osaka University, the laser with 4 beams and the total output of 10kJ/ps: LFEX has been built and we have started the integrated experiments. The experiments showed that the coupling efficiency is degraded because of the laser pre‐pulse. Namely, the main pulse is absorbed in a long scale pre‐plasma produced by the pre‐pulse and hot electron energy is higher than that for a clean pulse. Furthermore, the distance between the hot electron source and the core plasma is long. So, we are exploring how to overcome the pre‐pulse effects on the cone target. The next series of experiments is planned for this fall. In these experiments, the LFEX pre‐pulse level will be reduced and advanced targets for mitigating the pre‐pulse effects will be introduced.In this paper, it is proposed that a thin foil cover the l...