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A very high altitude survey of the effect of latitude upon cosmic-ray intensities - and an attempt at a general interpretation of cosmic-ray phenomena

Bowen, I. S. and Millikan, R. A. and Neher, H. Victor (1934) A very high altitude survey of the effect of latitude upon cosmic-ray intensities - and an attempt at a general interpretation of cosmic-ray phenomena. Physical Review, 46 (8). pp. 641-652. ISSN 0031-899X. doi:10.1103/PhysRev.46.641.

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The results of a very high altitude geographical survey extending in airplanes from Northern Canada to Peru, to altitudes of 22,000 feet, and, in three stratosphere flights made within the United States, to altitudes of 60,000 feet, are interpreted in the light of (1) the Epstein and the Lemaitre-Vallarta analysis of the effect of the earth's magnetic field, and (2) the Bowen-Millikan proof that the immediate agents responsible for the ionization of the atmosphere are electrons (+ and -), rather than protons or heavier nuclei. The main conclusions reached are: (1) that the resistance of the atmosphere to incoming electrons is 1 billion volts because of extranuclear encounters, 5 billion volts because of nuclear encounters; (2) that nuclear electron encounters produce only very soft secondaries, both photons and electrons; (3) that incoming photons produce most of the ionization found at sea-level or at sub-sea-level depths; (4) that nearly all of the non-field sensitive part of the ionization of the atmosphere above sea-level is due to photons of energy 200±170 million electron volts; (5) that in the equatorial belt a small part of the ionization is due to incoming secondary electrons of energies as high as 10 billion volts; (6) that these are responsible for the east-west effect and the longitude effect found in the equatorial belt; (7) that the field sensitive part of the ionization increases rapidly with increasing latitude in going from Panama to Spokane because incoming secondaries of energies decreasing from 8 billion to 2 billion volts get through the blocking effect of the field in rapidly increasing numbers with increasing latitude and add greatly in northern latitudes to the underlying ionization of the upper-air produced by the incoming photons; (8) that the only source now in sight of the observed cosmic-ray energies is matter-annihilation; (9) that the softest components of the cosmic rays have the energies corresponding to the partial annihilation or atom building hypothesis, while the hardest components have energies corresponding to the complete atom-annihilation hypothesis; (10) that these processes may conceivably be taking place (1) because of the very low temperatures that facilitate the clustering of hydrogen in interstellar space, or (2) because of such extreme temperature conditions of the opposite sort as are found in novae, as suggested by Zwicky.

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Additional Information:©1934 The American Physical Society. Received 24 July 1934. All of the foregoing work has been made possible through a grant from the Carnegie Corporation of New York, administered by the Carnegie Institution of Washington. We desire to express our deep appreciation for this assistance.
Issue or Number:8
Record Number:CaltechAUTHORS:BOWpr34e
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:5467
Deposited By: Tony Diaz
Deposited On:19 Oct 2006
Last Modified:08 Nov 2021 20:25

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