This project will research the relationship between incompressible and compressible magnetohydrodynamic (MHD) turbulence, including observable consequences in the solar wind, such as characteristic anisotropies in the inner wind and scalings of various fluctuations in the outer heliosphere. A transport theory for description of the long wavelength and low frequency variations of local MHD turbulence will be further exploited to address important observational issues in the solar wind. Extensions of this theory will describe assimilation of waves injected by wave-particle interactions associated with upstream waves, as well as waves associated with pickup and assimilation of newborn cometary and interstellar ions. Further work in basic MHD theory will include development and refinement of a phenomenology of MHD relaxation processes based upon an information-entropy description which has recently shown promise in the context of two dimensional hydrodynamics turbulence. Finally, the investigators will construct models for including turbulence effects in self- consistent models of solar wind acceleration, and self-consistent models for charged particle-wave turbulence dynamics near comets and shocks.
