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. Th ese N-body codes are of great importance for simulations in stellar dy namics and plasma physics. For systems with long-range forces, such as gravity or electromagnetic forces, it is important to increase the nu mber of particles to N greater-than-or-equal-to 107 particles. Signifi cantly improved modeling of N-body systems can be expected by increasi ng N, arising from a more realistic representation of physical transpo rt processes involving particle diffusion and energy and momentum tran sport. In addition, it will be possible to guarantee that physically s ignificant portions of complex physical systems, such as Lindblad reso nances of galaxies or current sheets in magnetospheres, will have an a dequate population of particles for a realistic simulation. Particle-m esh (PM) and particle-particle particle-mesh (P3M) algorithms present the best prospects for the simulation of large-scale N-body systems. A s an example we present a two-dimensional PM simulation of a disk gala xy that we have developed on the Connection Machine-2, a massively par allel boolean hypercube supercomputer. The code is scalable to any CM- 2 configuration available and, on the largest configuration, simulatio ns with N = 128 M = 2(27) particles are possible in reasonable run tim es.