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Implicit, perturbative algorithms [B. I. Cohen, A. M. Dimits, J. J. Stimson, and D. C. Barnes, Phys. Rev. E {bold 53}, 2708 (1996)] are extended to address electromagnetic particle simulation of drift-wave instabilities in electron and ion plasmas with a strong applied magnetic field. The algorithms use gyrokinetic ions and drift-kinetic electrons with a realistic mass ratio. Implicit moment and direct implicit solutions of the coupled Maxwell and plasma dynamical equations are demonstrated. Aspects of the numerical dispersion properties are confirmed in test simulations. Applications to ion-temperature-gradient and collisionless drift instabilities in a two-dimensional slab with magnetic shear are presented that illustrate the efficacy of the algorithms and the electromagnetic effects. {copyright} {ital 1997} {ital The American Physical Society}

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.}

Algorithms are presented for energy- and momentum-conserving like-particle Coulomb collisions in partially linearized ([delta][ital f]) particle simulations. They are developed and implemented in particular for gyrokinetic simulation models of a strongly magnetized plasma. The collision operators include both drag and diffusion terms, are not restricted to a single or few Fourier modes, and approximately conserve both momentum and energy locally in space in a statistical sense. The first algorithm is a many-mode generalization of a test-particle--plus--source algorithm previously proposed. The second is easier to implement and improves upon the first significantly by not requiring many time steps for good conservation. Implementations for the case for ion-ion collisions are given and conservation properties are demonstrated, both directly with non-self-consistent test simulation runs and indirectly with self-consistent runs. The computational cost of particle pushing and solving for fields depends on the relative collisionality and can result in a tripling of the total computational costs if collisions are done at each time step, but typically will be a small fraction of the total simulation cost. It is also shown that binary-collision-based algorithms are unsuitable for partially linearized simulations.