Cross-polarized electromagnetic backscatter from turbulent plasmas

Abstract

The cross section for the backscattering of cross-polarized electromagnetic radiation by an underdense plasma is calculated here by means of the second Born approximation. It is shown that when the dimensions of the scattering volume are much greater than the wavelength of the radiation and the correlation length of the plasma, the major contribution to the cross section arises from the asymptotic part of the four-point correlation function. The assumption that kV1/3 ≫ 1 also makes it possible to reduce the 6-dimensional integral to an integral over the direction of the intermediate scattering. This integral is carried out explicitly for some assumed correlation functions and some scattering volumes.