Article révisé par les pairs
Résumé : The behavior of electrostatic drift and ion sound waves is discussed in plasmas with an equilibrium density gradient both perpendicular and parallel to the ambient magnetic field. In spatially unlimited plasmas, and in Cartesian geometry, the mode amplitude is calculated for several profiles of the equilibrium density. Exact analytical solutions are found. Cylindric plasmas bounded in the radial direction and bounded or unbounded in the axial direction are also investigated in the presence of equilibrium density gradients in both the radial and axial directions. Exact analytical solutions are found in terms of the Kummer confluent hypergeometric functions, describing standing oscillatory patterns in the radial and axial directions, associated with the drift mode propagating in the poloidal (θ) direction. © 2007 American Institute of Physics.