STATIONARY MODES IN A NONNEUTRAL PLASMA

In a non-neutral plasma column of constant density it is shown that, f or certain parameter values, an infinitely degenerate internal mode, w hich has no variation in the axial direction, can be stationary in the laboratory frame. However, this mode cannot be driven resonantly by s tationary electric or magnetic field asymmetries. When the plasma dens ity is nonuniform the possibility of resonance of stationary field asy mmetries with the continuous spectrum is pointed out. (C) 1998 America n Institute of Physics.