MHD modeling of the solar wind with a north-south asymmetry
A. V. Usmanov and M. L.
Goldstein, NASA/Goddard Space Flight Center,
We present simulation results from a fully three-dimensional steady-state solar wind model with a magnetic field on the Sun composed of a tilted-dipole and a quadrupole. The quadrupole contribution is a source of north-south asymmetry and we study how the asymmetry translates into solar wind properties. The single-fluid MHD equations, which incorporate momentum and energy addition from Alfvén waves, are solved by a time-relaxation method in the region from 1-20 solar radii and by integration of steady-state equations along radius from 20 solar radii to 1 AU. We show that while a north-south asymmetry in plasma parameters persists up to 1 AU, the asymmetry in magnetic field intensity decreases with heliocentric distance and virtually disappears by about 10 solar radii.