Measuring the Angular Distribution of Cosmic Rays with a Telescope

The angular distribution of the secondary cosmic rays, mainly energetic muons, depends on the zenithal angle ϑ roughly as cos2 ϑ, as a consequence of the various physics processes taking place in the Earth atmosphere. The zenithal angular dependence of cosmic rays may be investigated even by a telescope made by two small Geiger counters, considering the limitations discussed in the previous Section. Examples of such measurements performed with different models of Geiger counters are presented and discussed in this Section.