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Author Webber, W. R.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ COSMIC NUCLEI ♦ ABUNDANCE ♦ CHEMICAL COMPOSITION ♦ COSMIC RAY DETECTION ♦ DATA ANALYSIS ♦ ISOTOPE RATIO ♦ SOLAR PARTICLES ♦ TELESCOPE COUNTERS ♦ COSMIC RADIATION ♦ DETECTION ♦ IONIZING RADIATIONS ♦ NUCLEI ♦ RADIATION DETECTION ♦ RADIATIONS ♦ SOLAR RADIATION ♦ STELLAR RADIATION ♦ Astrophysics & Cosmology- Cosmic Radiation
Abstract The relative charge abundance of galactic cosmic-ray nuclei has been measured between 600 and 1000 MeV per nucleon over a range of Z from 2 to 28. The abundances observed at Earth have been extrapolated to the cosmic-ray source yielding accurate source abundances for 15 elements. These abundances, along with recently measured isotopic abundance ratios are compared with the average abundances observed in another sample of accelerated material-solar cosmic rays. Significant differences are found in the composition for the elements He, C, N, and Ne. These galactic and solar cosmic-ray abundances are also compared with a variety of compilations of unaccelerated matter. This comparison is complicated by normalization problems for the O/Si ratio and by uncertainties compilations. In view of these difficulties, we have examined more carefully the very clear differences between the two accelerated species. At the present time, these differences seem to be explained more easily in terms of differing nucleosynthesis histories rather than preferential acceleration effects. The new galactic cosmic-ray source charge ratios presented here along with specific isotopic abundance differences that are observed require new calculations in the areas of both nucleosynthesis theory and the preferential acceleration and present a new challenge to the attempt to locate the source regions of galactic cosmic rays.
Educational Use Research
Learning Resource Type Article
Publisher Date 1982-04-01
Publisher Department Space Science Center, University of New Hampshire
Publisher Place United States
Journal Astrophys. J.
Volume Number 255
Issue Number 1
Organization Space Science Center, University of New Hampshire


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