Pitch angular dependence of cosmic rays modulation depth in the interplanetary space

The pitch-angular dependence of the galactic cosmic ray modulation depth in the Forbush has been investigated. The data of the stratospheric measurements, carried out in Norilsk on 15.12.71-28.12.71, have been used. Four height curves, showing the dependence of the secondary cosmic ray modulation amplitude, have been obtained. The spectrographic method has been used for data processing. It is shown that the particles with the pitch angles of THETA=π/2 have the most modulation, while those with the pitch angles of THETA=0 have the least modulation. The obtained results indicate, that during the Forbush period the modulation depth depends considerably on the pitch-angle of the cosmic particles in the interplanetary field