Acceleration and propagation of solar cosmic rays

Analysis of the solar cosmic ray measurements on the Geostationary Orbital Environmental Satellite (GOES) spacecraft indicated that the duration of solar flare relativistic proton large pulses is comparable with the solar wind propagation duration from the Sun to the Earth. The front of the proton flux from flares on the western solar disk approaches the Earth with a flight time along the Archimedean spiral magnetic field line of 15–20 min. The proton flux from eastern flares is registered in the Earth’s orbit 3–5 h after the flare onset. These particles apparently propagate across IMF owing to diffusion.