THREE-DIMENSIONAL MHD-NEUTRAL MODEL OF THE HELIOSPHERIC INTERFACE: INTERSTELLAR AND INTERPLANETARY MAGNETIC FIELD EFFECTS AND GMIR PROPAGATION

摘要

We present the results of a numerical simulation of GMIR propagation through a three-dimensional helio-sphere where the interface between the solar wind and the local interstellar medium is affected by the interstellar and interplanetary magnetic fields (ISMF and IMF). The magnetic and rotational axes of the Sun are assumed parallel. Modeling is performed on the basis of an MHD-neutral continuum model, where the systems governing the neutral and plasma fluids are connected via charge, momentum, and energy exchange. The ISMF orientation is chosen in a way favorable for the explanation of the space distribution of radio emission sources ahead of the heliopause. The heliosphere rotates in this case under the action of the magnetic field pressure. It also becomes asymmetric with respect to the solar ecliptic plane, while the heliospheric current sheet bends into one of hemispheres, depending on the IMF orientation. It is shown that propagation of GMIRs can create magnetic field barriers in the inner heliosheath, whose strength is greater than the IMF strength at the inner side of the heliopause for a corresponding background steady state. For plasma crossing the termination shock, the magnetic field is further increased. Perturbations of the heliopause result in the increase of the interstellar magnetic field in the outer heliosheath.