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An Application of the Direct Coulomb Electron Pair Production Process to the Energy Measurement of the "VH-Group" in the "Knee" Region of the "All-Particle" Energy SpectrumThe "all-particle" cosmic ray energy spectrum appears to be exhibiting a significant change in the spectral index just above approximately 3000 TeV. This could indicate (1) a change in the propagation of the cosmic rays in the galactic medium, and/or (2) the upper limit of the supernova shock wave acceleration mechanism, and/or (3) a new source of high-energy cosmic rays. Air shower and JACEE data indicate the spectral change is associated with a composition change to a heavier element mixture whereas DICE does not indicate this. A detector concept will be presented that utilizes the energy dependence of the production of direct Coulomb electron-positron pairs by energetic heavy ions. Monte Carlo simulations of a direct electron pair detector consisting of Pb target foils interleaved with planes of 1-mm square scintillating optical fibers will be discussed. The goal is to design a large area, non-saturating instrument to measure the energy spectrum of the individual cosmic ray elements in the "VH-group" for energies greater than 10 TeV/nucleon.
Document ID
Document Type
Reprint (Version printed in journal)
Derrickson, J. H.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Wu, J.
(Fayetteville State Univ. NC United States)
Christl, M. J.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Fountain, W. F.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Parnell, T. A.
(Alabama Univ. Huntsville, AL United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1999
Subject Category
Space Radiation
Meeting Information
International Cosmic Ray(Salt Lake City, UT)
Distribution Limits
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