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Observations of Low Energy Hydrogen and Helium Isotopes during Solar Quiet Times

Hurford, G. J. and Mewaldt, R. A. and Stone, E. C. and Vogt, R. E. (1973) Observations of Low Energy Hydrogen and Helium Isotopes during Solar Quiet Times. Proceedings of the 13th International Cosmic Ray Conference . pp. 93-98.

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We report a new quiet-time measurement of the relative abundance of cosmic-ray ^2H and ^4He. The observations were made in selected time intervals between September 1972 and February 1973 with the Caltech Electron/Isotope Spectrometer on IMP-7. In the energy interval 13-29 MeV/nucleon, we find an upper limit to the ^2H to ^4He ratio of Γ(^2H/^4He)< 0.06. This new upper limit is significantly lower than finite ^2H/^4He ratios measured in earlier years by other workers. Possible implications of this new result are discussed.

Item Type:Article
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URLURL TypeDescription Technical Reports Server (NTRS)
Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
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Additional Information:© 1973 University of Colorado. Provided by the NASA Astrophysics Data System. This work was supported in part by NASA under contract NAS5-11066 and Grant 05-002-160. One of us (Hurford) received support from the National Research Council of Canada while another (Stone) was an Alfred P. Sloan research fellow during this period. Space Radiation Laboratory SRL ID #: 1973-05
Group:Space Radiation Laboratory
Funding AgencyGrant Number
National Research Council of Canada (NRCC)UNSPECIFIED
Alfred P. Sloan Research FellowshipUNSPECIFIED
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1973-05
Record Number:CaltechAUTHORS:20140409-085000539
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:44804
Deposited By: SWORD User
Deposited On:10 Apr 2014 20:45
Last Modified:20 Feb 2020 14:33

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