A UNIFIED MONTE-CARLO INTERPRETATION OF PARTICLE SIMULATIONS AND APPLICATIONS TO NONNEUTRAL PLASMAS

Using a ''Monte Carlo interpretation'' of particle simulations, a gene ral description of low-noise techniques, such as the deltaf method, is developed in terms well-known Monte Carlo variance reduction methods. Some of these techniques then are applied to linear and nonlinear stu dies of pure electron plasmas in cylindrical geometry, with emphasis o n the generation and nonlinear evolution of electron vortices. Long-li ved l=1 and l=2 vortices, and others produced by unstable diocotron mo des in hollow profiles, are studied. It is shown that low-noise techni ques make it possible to follow the linear evolution and saturation of even the very weakly unstable resonant diocotron modes.