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Further tests of the atom-annihilation hypothesis as to the origin of the cosmic rays

Millikan, R. A. and Neher, H. Victor and Pickering, William H. (1943) Further tests of the atom-annihilation hypothesis as to the origin of the cosmic rays. Physical Review, 63 (7-8). pp. 234-245. ISSN 0031-899X. doi:10.1103/PhysRev.63.234.

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1. Tests in Mexico. The authors had predicted that since the hypothetical silicon-annihilation rays should have enough energy (13.2 Bev) to get vertically through the earth's magnetic field at the equator in Peru, though not in India, there should be found, both at sea level and at all altitudes in the Americas, when vertically incoming rays alone are under test, a very long plateau of uniform cosmic-ray intensities extending north from Mollendo, Peru to about the latitude of Victoria, Mexico (mag. lat. 32.8°). There the strong band due to oxygen annihilation rays (7.5 Bev) should first appear, to be followed in going still further north when the latitude of 40° N magnetic had been reached, by the full entrance of the nitrogen annihilation band (6.5 Bev). The experimental findings were in accord with these predictions. 2. Tests in the United States. In going from Pasadena (mag. lat. 40.7° to St. George, Utah, but 4.1° (280 miles) nearer to the N magnetic pole than Pasadena, the carbon-annihilation band (5.6 Bev) was expected to appear, to be followed by a flat plateau clear up to latitude 54° N magnetic, when helium annihilation rays (1.88 Bev) were expected to appear. A ballon flight at St. George (mag. lat. 44.8°) and another at Pocatello, Idaho (mag. lat. 51°) yielded preliminary results in harmony with these predictions. 3. Evidence that the act of atom-annihilation actually transforms the rest mass energy of an atom into an electron pair. The flat plateau between St. George and Pocatello (mag. lat. 51°) corresponding to the absence of abundant atoms of atomic weight between that of carbon and that of helium, and the definite appearance of a new band between Omaha (mag. lat. 51.3°) and Bismarck (mag. lat. 56°) constitute new and strong evidence for the transformability of the complete rest mass energy of an atom into an electron pair.

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Additional Information:©1943 The American Physical Society. Received 28 January 1943. The foregoing investigations and a long series of preceding ones upon which these depend have been supported for years by grants from the Carnegie Corporation of New York administered by the Carnegie Institution of Washington. For this aid the authors wish to express their keen appreciation. They wish also to make acknowledgments to the Indian Meteorological Service for cordial and well-nigh unlimited assistance to their work in India and also to express their thanks for similar cooperation in Mexico by the Mexican Meteorological Service.
Issue or Number:7-8
Record Number:CaltechAUTHORS:MILpr43
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:6688
Deposited By: Tony Diaz
Deposited On:18 Dec 2006
Last Modified:08 Nov 2021 20:36

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