A global model of the heliosphere that includes turbulent heating of the solar wind

Melvyn L. Goldstein, Arcadi V. Usmanov, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA

We have developed a magnetohydrodynamic model to simulate the global steady-state structure of the solar wind in the region from 0.3 to 100 AU. The model is based on a numerical solution of the combined set of solar wind equations and small-scale turbulence transport equations and accounts for apparent heating of the solar wind by a turbulence cascade. Interstellar pickup protons are included as a source term. We use the model to study the distribution of plasma and magnetic field parameters and the effects of turbulence dissipation and pickup-proton-associated-heating on the variation of plasma temperature in the outer heliosphere. To illuminate the roles of the turbulent cascade and the pickup protons in heating the solar wind with heliocentric distance, we compare the model results with and without turbulence. The variations of plasma temperature in the outer heliosphere are compared with Voyager 2 observations.