On the relation between solar wind structure and solar wind rotational and tangential discontinuities

Abstract

Solar wind plasma and magnetic field data were used to identify rotational and tangential discontinuities during the first 40 days of the flight of Mariner 5. Of the 40 rotational discontinuities found, 36 were clustered in three distinct 3- to 6-day intervals. These three intervals were characterized by high solar wind bulk velocities, high magnetic field magnitudes, low densities, high correlation between velocity and magnetic field changes, and the presence of smooth Alfven waves. The rotational discontinuities had magnetic field changes that were generally close to the direction of magnetic field changes for smooth Alfven waves. Although the primary component of these changes was perpendicular to the equatorial plane for both, the radial component for the discontinuities was generally larger. The normals to the tangential discontinuity surfaces strongly preferred a direction near the ecliptic plane and perpendicular to the spiral field direction.