Illumination and energy deposition in a multibeam laserhyphen;fusion system

摘要

Calculations are presented for multibeam laserhyphen;fusion systems illuminating spherical targets. Both the illumination pattern and the energy deposition on the surface of the target are obtained, with the beam focus in general displaced from the center of the target. The absorptivity (which depends on angle of incidence and polarization) is discussed from experimental and theoretical evidence. Numerical results are displayed for two LASL laser systems. They illustrate the distinction between the symmetry of the illumination and of the energy deposition. They also demonstrate, as a function of the relative size of the target and of the (finite) focal spot, that the absorption can be enhanced by displacing the beam axis from the center of the target.