Authors: D. Odstrcil; M. Vandas; C.N. Arge; and V.J. Pizzo
Affiliation: CIRES, University of Colorado; Astronomical Institute, Prague,
Czech Republic; Air Force Research Laboratory; National Oceanic and Atmospheric
Administration, Space Environment Center
A halo coronal mass ejection (CME) observed on May 12, 1997 is a well-defined event characterized by a relatively quiet solar and interplanetary background into which the ejecta was launched. This event has been selected to start with the detailed numerical modeling of Sun-to-Earth events. Critical part in this effort is the specification of appropriate time-dependent boundary conditions near the Sun capable to drive 3-D magnetohydrodynamic models. Our approach to the problem is based on the following approximations: (1) the ambient solar wind is derived from coronal models utilizing photospheric magnetic field observations; (2) global properties of the CME are derived from geometrical and kinematic fitting of coronagraph observations; and (3) internal magnetic structure of the CME is specified by a 3-D analytic flux rope model. We will present our recent results of heliospheric simulations, with a special attention being given to the interaction of the transient disturbances within the streamer belt and to comparisons with near-Earth observations.