Observing the East–West Cosmic Ray Asymmetry

The azimuthal angular distribution of the secondary charged cosmic radiation at sea level or moderate altitudes is characterized by a slight East–West asymmetry, produced by the Earth magnetic field acting on the charged particles of the cosmic radiation. Evidence of such effect may be obtained by precision measurements of the cosmic ray flux from the East and West directions, and to some extent even a small telescope of Geiger counters, as discussed in the present Section, could be able to show the asymmetry.