Harmonics of daily variations and spatial variation of the cosmic raycurrent.

It has been shown in an earlier study (Dolginov and Melnikov, 1981) that the second, third, and fourth harmonics of the daily variations of cosmic rays with energies of 50-200 GeV are related to the spatial derivatives of the cosmic ray current. The formulas proposed in the above study are not sufficiently accurate since they neglect the currents normal to the regular magnetic field. On the basis of the conditions of cosmic ray propagation in the interplanetary space, more accurate formulas are obtained in the present study for the relative magnitudes of the second, third, and fourth harmonics of the daily variations.