The Nature of the Primary Cosmic Radiation and the Origin of the Mesotron

This chapter focuses on the nature of the primary cosmic radiation and the origin of the mesotron. The chapter describes certain measurements of the vertical intensity and the production of mesotrons at high altitudes in which various arrangements of counters in three-, four-, or fivefold coincidences were used. The vertical intensity was obtained with lead thicknesses of 4, 6, 8, 10, 12, and 18 cm interposed between the counter tubes. The chapter illustrates the combined results of these experiments. It was seen from these measurements that the intensity of the hard component increased continuously to the highest altitudes reached. It was also found that measurements of the hard component made at very high altitudes with lead thicknesses even as small as 4 cm were not appreciably affected by electrons.