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Note on the nature of cosmic rays

Epstein, Paul S. (1930) Note on the nature of cosmic rays. Proceedings of the National Academy of Sciences of the United States of America, 16 (10). pp. 658-663. ISSN 0027-8424. doi:10.1073/pnas.16.10.658.

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The recent experiments of Bothe and Kolhoerster(1) have led to an important and interesting conclusion. The ionization phenomena, by means of which cosmic rays are measured, are produced by highly penetrating corpuscular rays. It remains, however, an open question whether this corpuscular radiation is identical with the cosmic rays themselves, or is secondary in its nature, produced by primary rays of an electromagnetic character. Bothe and Kolhoerster admit both possibilities, but they seem to lean toward the first, owing to the fact that their corpuscular rays show a penetration of the same order of magnitude as that of the cosmic rays themselves.

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Additional Information:© 1930 by the National Academy of Sciences. Communicated August 19, 1930.
Issue or Number:10
Record Number:CaltechAUTHORS:EPSpnas30b
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7665
Deposited By: Tony Diaz
Deposited On:21 Mar 2007
Last Modified:08 Nov 2021 20:44

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