Journal of Plasma Physics


Scintillations in a magnetized plasma. Part 2. The fourth-order moment

D. B. Melrosea1

a1 Research Centre for Theoretical Astrophysics,University of Sydney, NSW 2006, Australia


The theory of strong scintillations in a weakly anisotropic plasma is used to derive an equation satisfied by the correlation functions for the Stokes parameters. The coefficients that describe these correlation functions are determined explicitly in terms of a matrix generalization of the standard phasestructure function. In discussing implications of the theory, emphasis is placed on terms that have no counterpart in an isotropic plasma. It is shown that the decay of the linear polarizaiton that results from differential Faraday rotation is different in the mean squares and the square means of the Stokes parameters. In principle, this allows one to determine properties relating to the fluctuations of the magnetic field along the ray path. A formal treatment of polarization dependent intensity fluctuations in a magnetized plasma is presented and discussed briefly.

(Received June 11 1993)