A Preliminary Directional Study of Cosmic Rays at High Altitude. II. Experimental Results and Interpretation

The zenithal distribution of particles at high altitudes observed with counter telescopes has been compared with simple calculations concerning the multiplicity and angular divergence of secondary particles. The observations are in agreement with a sharply collimated forward type of production event, and disagree with the wide angle type of production of hard secondaries. The azimuthal distributions and zenithal distributions indicate a nearly isotropic primary flux, in agreement with geomagnetic considerations at geonetic latitude 56^∘{}N. The effects of the atmosphere on directional asymmetry measurements at 13-g/cm² atmospheric depths are concluded to be small, especially if lead filters of a few cm thickness are used. The number of low energy particles is small at this depth.