Numerical analysis on stability of laser-driven-pellet implosion

The dynamical stability of the implosion of a laser-driven pellet is investigated by using the linearized three-dimensional and nonlinear two-dimensional hydrodynamic equations. In these calculations, the following conclusions are obtained: 1) The growth rate of a perturbation is very sensitive to the way how the laser energy is supplied in time into the pellet. 2) The region where the perturbation has a positive growth rate varies with the wave length of the perturbation. 3) The growth of a perturbation is sensitive to the pellet structure. 4) Nonlinear mechanisms have a tendency to stabilize the perturbations. (auth.)