Geometric optics in plasmas characterized by non-Hermitian dielectric tensors

This paper presents a generalization of the theory of geometric optics in plasmas where the local dielectric tensor ε(k→,ω;r→,t) is not almost Hermitian, as heretofore assumed. It is shown that for general ε one can construct the formalism so that the new theory is characterized by the same equations determining the rays, and the equation for the amplitude of the wave along the rays is unmodified in structure. The theory uses the quasidispersion relation det{ε(k→,ω+iν;r→,t)•[ε(k→,ω-iν; r→,t)]*}=0 to find the complex roots ω+iν, where when the approximation of short wavelength compared with the scale length underlying geometric optics holds, the real part ω serves to generate the rays via r→=ωk→, and the imaginary part iv enters the transport equation for the amplitude.