Geomagnetic effects on cosmic ray propagation for different conditions

The geomagnetic field (B_geo ) sets a lower cutoff rigidity (R_c ) to the entry of cosmic particles to Earth which depends on the geomagnetic activity. From numerical simulations of the trajectory of a proton (performed with the MAGCOS code) in the B_geo , we use backtracking to analyze particles arriving at the Auger Observatory location. We determine the asymptotic trajectories and the values of R_c in different incidence directions. Simulations were done using several models of B_geo that emulate different geomagnetic conditions.