Specific features of magnetic barrier formation near the magnetopause

The numerical three-dimensional MHD model is used to study the formation of the magnetic barrier in the inner part of the magnetosheath near the magnetopause. The set of the quasistationary solutions for several characteristic directions of the interplanetary magnetic field (IMF) has been obtained: for northward and southward IMF, for the direction along the Parker helix (at an angle of 45° with respect to the Sun-Earth line), and for the predominantly radial direction (at an angle of 20° with respect to the Sun-Earth line). The mechanism used to take into account the effect of magnetic reconnection at the magnetopause on a flow in the magnetosheath is introduced in the case of southward IMF. The results of the calculations indicate that the magnetic field absolute value in the magnetic barrier reaches its maximal value when IMF is northward. The introduction of magnetic reconnection at southward IMF can result in an insignificant decrease in the field value. However, the model predicts that a decrease in the magnetic field is much more substantial when the IMF direction is close to radial.