Very High Energy Cosmic Rays

Abstract

Results from ground level and underground experiments on cosmic rays with energy 1012 to 1020eV are reviewed. They show that the energy spectrum has two significant features, a ‘knee’ and an ‘ankle’. The arrival directions of these cosmic rays at the solar system are anisotropic, features of the anisotropy appearing to be correlated with features of the spectrum. Detailed interpretation of this information awaits conclusive evidence regarding the composition of these cosmic rays. New results and prospective new results on the composition are described and discussed.