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Solar cycle modulation of Galactic protons and electronsIt is demonstrated here, through a detailed application of the model of Perko and Fisk (1983), that the cyclic variation in the cosmic ray spectra, the gradient, and the hysteresis, all in the ecliptic plane, can be caused by the accumulated effect of strong scattering regions moving out from the sun. The proton data in the form of spectral ratios, considered to be signatures of drifts, can be simply explained in terms of hysteresis effects, although a charge-dependent effect cannot be ruled out. It is also shown that cosmic ray recovery in this model can occur immediately after a sudden intensity decrease without requiring the disturbance to weaken as it propagates away; however, it is an energy-dependent recovery, a result of diffusive propagation inward, which partially contradicts data gathered at 1 AU. The cosmic ray intensity profiles at 1 AU may result from mechanisms different from those that exist beyond several AU.
Document ID
19870064413
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Perko, John S.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 13, 2013
Publication Date
August 1, 1987
Publication Information
Publication: Journal of Geophysical Research
Volume: 92
ISSN: 0148-0227
Subject Category
Space Radiation
Report/Patent Number
ISSN: 0148-0227
Accession Number
87A51687
Distribution Limits
Public
Copyright
Other

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