Multicomponent Beam-Plasma Waves

The linearization procedure is applied to the equations governing a beam-plasma system, in which the stream velocities and the wavevector are parallel to the external magnetic induction. No special constraints are imposed on the parameters characterizing the constituent fluids in the equilibrium state of this macroscopic picture. From the MAXWELL equations an expression for the electromagnetic field of the wave is obtained and substituted in the equations of motion. The components of the first-order pressure tensors are computed in the low-temperature approximation, but without recurring to the strong magnetic induction CGL hypothesis. Since the equations of motion are now expressed only in the components of the perturbations of the drift velocities, the dispersion relations follow immediately. These relations are applicable to all beam-plasma systems comprised between the now conventional multicomponent plasma and the system of beams of charged particles. Some known cold beam-plasma cases are included in the general dispersion equations.