Letter | Published:

Detection of Relativistic Solar Particles before the Hα Maximum of a Solar Flare


WE report here the first direct detection of relativistic solar protons before the Hα maximum phase of a solar flare and in near coincidence with the maximum phase of the white-light flare. These observations have important implications for theories of particle acceleration during flares and for the appropriate particle injection times to be used in the modelling of solar particle events by diffusion theories.

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