Implicit-moment, partially linearized particle simulation of kinetic plasma phenomena

An algorithm for kinetic simulation of electron and ion plasmas is introduced that combines both implicit and perturbative methods to deal efficiently with disparate time scales and signal-to-noise issues associated with particle discreteness. The algorithm is introduced for an electrostatic model in a strong magnetic field with gyrokinetic ions and drift-kinetic electrons. Some of the numerical dispersion properties are analyzed and confirmed in test simulations. Two-dimensional applications of the algorithm to drift-wave instabilities excited either by an ion temperature gradient (ion-temperature-gradient instability) or by electron inverse Landau damping in the presence of a density gradient (collisionless drift instability) are presented that illustrate the usefulness of the method. Clear gains in resolution and computational efficiency over previous methods are achieved. {copyright} {ital 1996 The American Physical Society.}