IMPLEMENTATION OF PARTICLE-IN-CELL STELLAR DYNAMICS CODES ON THE CONNECTION MACHINE-2

The development of massively parallel supercomputers provides a unique opportunity to advance the state of the art in N-body simulations. These N-body codes are of great importance for simulations in stellar dynamics and plasma physics. For systems with long-range forces, such as gravity or electromagnetic forces, it is important to increase the number of particles to N greater-than-or-equal-to 107 particles. Significantly improved modeling of N-body systems can be expected by increasing N, arising from a more realistic representation of physical transport processes involving particle diffusion and energy and momentum transport. In addition, it will be possible to guarantee that physically significant portions of complex physical systems, such as Lindblad resonances of galaxies or current sheets in magnetospheres, will have an adequate population of particles for a realistic simulation. Particle-mesh (PM) and particle-particle particle-mesh (P3M) algorithms present the best prospects for the simulation of large-scale N-body systems. As an example we present a two-dimensional PM simulation of a disk galaxy that we have developed on the Connection Machine-2, a massively parallel boolean hypercube supercomputer. The code is scalable to any CM-2 configuration available and, on the largest configuration, simulations with N = 128 M = 2(27) particles are possible in reasonable run times.