Excitation of slow cyclotron waves by an ion beam in a polyhelical relativistic electron beam

Consideration is given to a means for the excitation of slow cyclotron waves for autoresonant ion acceleration which is based on the development of instabilities in a polyhelical relativistic electron beam. Examination of the linear stage in the development of a beam instability upon the propagation of a narrow monoenergetic ion beam in a tubular polyhelical relativistic electron beam propagating in a waveguide shows that the increment in beam instability may be greater when the initial transverse momentum of the relativistic beam is nonzero than in a relativistic beam with zero initial transverse momentum, as in present systems.