Instabilities and Turbulence: Summary Report


  • P. E. Vandenplas


R. J. Forrest (University College, London) examined the relation existing between various theories of helical propagation along a weakly ionized plasma column in an axial magnetic field. He showed that these particular theories are limiting cases of a general theory which includes both the effects of ion inertia and the influence of the magnetic field on the ions. The theory uses the first two fluid equations for the perturbed quantities of a warm plasma, i.e., the first two moments of the Boltzmann equation. For simplicity the model used is a planar one in which the perturbed densities and velocities for electrons and ions are introduced together with an electrostatic potential.