On diaphragming of a particle flux entering the magnetosphere slits

Two models of the magnetospheric slit (polar cusp) are considered. In the first model the magnetospheric field has the form of the ideal dipole and it is not bounded. Particles, instance solar cosmic beams, fly from infinity and enter the magnetosphere along the dipole neutral line. This model corresponds to the open magnetosphere model. In the second model the magnetospheric field has the form of the ideal dipole and at some distance from the centre it is sharply bounded by the magnetic pause. At the magnetic pause the field changes stepurse. The solar particles flying from infinity enter the magnetosphere along the neutral line. This model corresponds to the closed magnetosphere model. The estimations obtained of the magnetic diaphragm have shown that the geomagnetic field strongly diaphragm the flux of entering solar cosmic beams