Macroscopic stability of rotating and propagating LIB

The linear stabilities of a rotating and propagating light ion beam in a low-density plasma are studied numerically on the basis of the hydromagnetic equations. The centrifugal force acts on the beam and the self-magnetic fields are induced by the rotating and propagating charged particles. To clarify the physical mechanism, a simple model characterizing a rotating and propagating beam is utilized, and it is found that the centrifugal force and the magnetic field in the azimuthal direction play a role of stabilization. Under such beam parameters which are practically required for the energy driver for inertial confinement fusion, the numerical results indicate that the beam in the equilibrium state is stable if the ratio of the beam-roatating velocity to the propagating one is more than the value of 0.8. (author)