Abstract
We calculate the orbits of the low-energy solar cosmic ray particles in the earth's dipole magnetic field and then estimate on their asymptotic velocity vectors before entering this magnetic field. Although the incident region of these particles is restricted in the area of higher geomagnetic latitudes than 60°, it is clear that there are anisotropic effects, i. e. impact zone effects for the incidence of these particles. Furthermore, the precipitation lines of the incidence will be shown to be circular around the geomagnetic north pole.
Next, it will be shown from the comparison of the calculated results with the observed data that, in the initial stage of the incidence, these low-energy cosmic ray particles tend to impinge upon the earth anisotropically, in accordance with the expectation from the calculated results, and that, slightly before the onset of geomagnetic Sc storms, their anisotropic incidence changes into isotropic one, although there are some exceptional cases. Finally, criticisms and a possible explanation on the features of their incidence after the onset of geomagnetic Sc storms will be proposed.
