Ion-beam plasma interaction in ion fast ignition nuclear fusion scheme: a systematic study of the hot-spot properties and gains

Abstract

Ion fast ignition by laser-driven ion beams is an interesting approach within the inertial confinement fusion scheme to achieve nuclear fusion. In the ion fast ignition, once the precompression of the target is finished, a sphere of fully ionized deuterium-tritium (DT) is obtained. In this work, we have investigated the following stages: heating of the DT sphere by a monoenergetic ion beam and the preliminary evolution of the plasma. To this end, we have carried out a systematic numerical study in terms of the beam parameters (ion fluence and projectile energy), the temperature fields obtained in the plasma, the self-heating, ignition and burning gains, as well as the characteristic lengths and temperatures of the heated plasma and the hot spots generated during the beam-plasma interaction, considering three beams of ions with different charges (p+,C6+, and V23+). This study allows us to determine the beam parameter space in which hot spots are generated and ignition is achieved. In addition, we have also studied the effect of the plasma corona surrounding the core and the presence of impurities in the plasma on the parameters mentioned above. Since in both cases the slowing down of the ion beam is increased with respect to the pure DT ideal core, the beam parameter space is shifted toward higher values of the ion fluence and projectile energy.