Threedimensional magnetic field configurations in the heliosphere
Abstract
We obtain a class of steady threedimensional magnetohydrodynamic (MHD) solar wind solutions from a primary radial MHD wind which is spherically symmetric. The energetic source for modifying the given primary MHD wind is the Poynting flux into the solar corona due to interactions of rotation, random flows, and magnetic field at the solar surface. The total energy flux associated with the perturbative MHD flow is conserved beyond several solar radii for typical solar wind parameters. Our main results are as follows: (1) clarification of the issue of possible transverse magnetic field configurations in heliospheric polar regions which can significantly influence the transport of galactic cosmic rays; (2) explicit demonstration that in the presence of nonaxisymmetric MHD perturbations over the solar poles such as a typical misalignment of the rotation and magnetic axes as well as random MHD perturbations, the transverse magnetic field eventually dominates the radial component over the polar heliosphere at large radial distance; (3) an analytical MHD model for latitudinal variation of heliospheric magnetic field due to the solar differential rotation; and (4) a MHD model of a warped heliospheric current sheet and its deformation due to the solar differential rotation. Our class of MHD wind solutions provides a new theoretical basis for developing numerical MHD codes and for modeling modulation of galactic cosmic rays by the heliospheric magnetic field.
 Publication:

Journal of Geophysical Research
 Pub Date:
 November 1992
 DOI:
 10.1029/92JA01602
 Bibcode:
 1992JGR....9717183L
 Keywords:

 Heliosphere;
 Magnetic Field Configurations;
 Magnetohydrodynamic Flow;
 Solar Magnetic Field;
 Three Dimensional Models;
 Galactic Cosmic Rays;
 Magnetohydrodynamics;
 Radiation Transport;
 Small Perturbation Flow;
 Solar Wind;
 Solar Physics;
 Interplanetary Physics: Interplanetary magnetic fields;
 Interplanetary Physics: Solar wind plasma;
 Interplanetary Physics: Cosmic rays;
 Solar Physics;
 Astrophysics;
 and Astronomy: Magnetic fields