On the Issue of Damping of a Transverse Ion Bernstein Wave in an Inhomogeneous Magnetic Field

Abstract

With allowance for the centrifugal and gradient drifts of ions, a new approximate dispersion equation is obtained for the ion Bernstein (IB) wave propagating strictly transverse to the external inhomogeneous magnetic field. Using this equation, it is shown that if, in the high-temperature plasma, the drift of ions is taken into account, the resonance frequency ranges in the vicinities of the ion cyclotron frequency harmonics can strongly overlap. In this case, the ion Bernstein waves turn out to be strongly damped, despite the absence of the longitudinal component of the wave vector.