Evolution of Abundances and Spectra in the Large Solar Energetic Particle Events of 1998 Sep 30 and 2000 Apr 4
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چکیده
The 1998 Sep 30 and 2000 Apr 4 events are both large western solar energetic particle (SEP) events, in which 1 MeV proton intensities exceed 10 particles (cm s sr MeV) . Yet they exhibit quite different time variations of elemental abundance ratios and energy spectra. Using a model of SEP transport through self-amplified interplanetary Alfvén waves, we fit the simultaneous observations of protons and ions of helium, oxygen, and iron. We conclude that wave amplification by high energy protons largely account for the differences in the observed time histories.
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تاریخ انتشار 2014