Magnetohydrodynamic modeling of the solar corona during Whole Sun Month

The Whole Sun Month campaign (August 10 to September 8, 1996) brought toget her a wide range of space-based and ground-based observations of the Sun an d the interplanetary medium during solar minimum. The wealth of data collec ted provides a unique opportunity for testing coronal models. We develop a three-dimensional magnetohydrodynamic (MHD) model of the solar corona (from 1 to 30 solar radii) applicable to the WSM time period, using measurements of the photospheric magnetic field as boundary conditions for the calculat ion. We compare results from the computation with daily and synoptic white- light and emission images obtained from ground-based observations and the S OHO spacecraft and with solar wind measurements from the Ulysses and WIND s pacecraft. The results from the MHD computation show good overall agreement with coronal and interplanetary structures, including the position and sha pe of the streamer belt, coronal hole boundaries, and the heliospheric curr ent sheet. From the model, we can infer the source locations of solar wind properties measured in interplanetary space. We find that the slow solar wi nd typically maps back to near the coronal hole boundary, while the fast so lar wind maps to regions deeper within the coronal holes. Quantitative disa greements between the MHD model and observations for individual features ob served during Whole Sun Month give insights into possible improvements to t he model.