Controlled sustained nuclear fusion for power generation has been an international research goal for decades. A number of different approaches have been proposed both in theory and experiment. Most of them feature a hot plasma of hydrogen confined in a magnetic bottle, as in a star. Lasers can provide a way of triggering the nucleosynthetic reactions. This paper describes the simulation of how a laser propagates through plasma. Discovering what happens in the process is important in understanding how energy is delivered to the plasma by the laser; how the laser is diffracted, scattered, and deflected; and how the plasma behaves after it interacts with the laser.

This model is extensive. It includes the fluid dynamics of the plasma, the laser field, and inhomogenieties in the plasma. All the equations governing the behavior of the components of the model are presented, and references to the literature are extensive. The simulation uses an adaptive mesh based on elongated cells, representing the time scales of the changes in the direction of laser propagation and those perpendicular to it. Together they appear as bundles of pencils. Boundary conditions are based on perfectly matched layers to avoid spurious reflections caused by numerical artifacts. The entire calculation is implemented on a large parallel processing system. Numerical experiments with up to 500 million cells are carried out and reported.

Researchers in laser fusion would be the primary readers of this paper. Scientists modeling the behavior of lasers interacting with matter are also likely to find this paper useful.