Study of the 3-D Reconstruction of Heliospheric Vector Magnetic Fields From Faraday-Rotation Inversion

摘要

One of the most-sought heliospheric parameters is the vector (three- component) magnetic field. The magnitude and direction of magnetic field is of interest scientifically as parameters that characterize the heliosphere and relate outward-flowing solar wind plasma to the density and velocity structures that provide its transport. Moreover, it is this field that interacts with other objects imbedded in the interplanetary medium. For the Air Force, these interactions are of primary interest at Earth where a southward interplanetary magnetic field (Bz negative) can couple with the Earth's magnetic field at the boundary of the magnetosphere, causing geomagnetic storms. In addition, solar energetic particles (SEPs) which account for some of the most damaging radiation hazards to high-flying aircraft and astronauts are confined to magnetic fields that connect Sun with Earth. At UCSD we have provided an inversion mechanism that can remotely determine heliospheric vector magnetic fields, their strength, and location in 3-D, and provided a mechanism to image these. We have also shown how these can be modeled, extrapolated, and refined in 3-D using MHD simulations. In addition we have developed an extension to the UCSD 3-D inversion technique that allows far more accurate forecasts of these vector fields prior to their Earth-arrival.