Аннотация:The method of the analysis of data on vertical rigidities of cosmic rays cutoff is presented
based on the particle trajectory calculations in the geomagnetic field described by the Tsyganenko-89
model. The essence of the method consists in the fact that both the experimental data and the calculation
results are described in the form of change of their value relative to the values related to IGRF. The value
of these relative changes quite certainly depends on the rigidity itself and on the level of geomagnetic
field disturbance (the K
p-index). The proposed model well describes calculation data and agrees with the
results of cutoff rigidity measurements carried out on satellites.