30TH INTERNATIONAL COSMIC RAY CONFERENCE Persistent energetic He in the inner heliosphere
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چکیده
Using data from the Solar Isotope Spectrometer on NASA’s Advanced Composition Explorer spacecraft we have examined the time and energy dependence of the quiet-time 5–15 MeV/nuc He intensity from 1998 through 2006 in order to establish the origin of these particles. We find a mixed population, with He from impulsive solar energetic particle events dominating at the lower end of this energy interval and galactic secondary He becoming significant at the high end.
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تاریخ انتشار 2015