The Simulation of Solar Wind Turbulence within Corotating Interaction Regions near 1 AU

Abstract:

Modulation of the galactic cosmic rays inside the corotating interaction regions is driven in major part by solar wind turbulence. The foregoing slow stream and the following fast stream within a corotating interaction region form a shear layer between these streams. The shear is considered to be one of the principal sources of the turbulence in solar wind. Observations show that the turbulent properties of the slow and fast streams within the CIRs are quite different. We performed MHD simulations of the solar wind plasma and turbulent properties inside the corotating interaction regions for radial distances of 0.3 AU to 1.5 AU. The results of the simulations are compared and validated with observations from the most two recent solar minima, including the total turbulent energy, cross helicity, residual energy, and the respective correlation lengths. These results will be applied to a similar model for a full scale heliosphere for investigating the effects of the solar wind turbulence on propagation and modulation of galactic cosmic rays.