Stability of propagating long ion ring layer

An energy principle is developed to derive a sufficient condition for treating the low frequency stability of an axi-symmetric infinitely-long rotating ion layer which propagates along the axis. This kind of a long ion layer may be used as an energy deriver in LIB-ICF. Ion Particles that carry both the axial and azimuthal currents are described in the Vlasov formalism while the motion of background plasma is approximately analyzed by using the two-fluid equations. Stability boundaries are plotted in a parameter space regarding an ion layer propagating in the rarefied plasma. (author)