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Points from Foregoing Letters

    Naturevolume 140page31 (1937) | Download Citation



    Measurements of cosmic ray intensities at various atmospheric heights, at Madras, India and San Antonio, Texas, indicate, according to Prof. I. S. Bowen, Prof. R. A. Millikan and Dr. H. V. Neher, that the incident cosmic rays produce their maximum ionization before they penetrate more than one tenth of the atmosphere. The authors deduce, from the absorption coefficient down to sea-level, that the particles in the cosmic rays are predominately positive electrons, not protons.

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