The Influence Gradient Drift in the Interplanetary Magnetic field (IMF) on the Spectra of Solar Energetic Protons (SEP) at Earth as a Function of Heliographic Latitude

Abstract:

Solar Energetic Particles (SEP) consists of Protons, Electrons and Ions accelerated in Solar flares and/or Coronal Mass Ejections (CME’s). Current models for the interplanetary transport of SEPs neglect the effect of magnetic gradient drift because other effects are thought to dominate.

This may not be the case for high energy SEPs. We report an experimental test for evidence of magnetic gradient drift using high energy proton data from large SEPs from Goddard Medium Energy (GME) on IMP-8 and the Energetic Particle System (EPS) on GOES. We identified the SEPs with measured proton fluxes above 50 MeV and measured their spectra. We also identified the hemispheric coordinates of the sites where these events originated. We compared the event-integrated proton differential energy spectra from the northern and southern hemispheres of the sun to search for difference that could be ascribed to the effects of magnetic gradient drift. The results of this comparison will be presented.