PROPAGATION CONDITIONS OF RELATIVISTIC ELECTRONS IN THE INNER HELIOSPHERE

The intensity and anisotropy time profiles of six relatively small relativistic electron events observed within 0.65 AU by one of the Helios spacecraft were fitted with the model of focused transport under the assumption of a particle mean free path-lambda independent of the radial distance. For approximately 0.5 MeV electrons we find that the amount of interplanetary scattering varies from one solar event to the other, with local mean free paths-lambda between 0.02 and 0.15 AU. Comparison with previous results obtained close to 1 AU shows that there is no marked variation in the average scattering conditions with radial distance. The amount of scattering for the small electron events presented in this study is not markedly smaller than for large events. This suggests that in this energy range the effects of additional turbulence generated by the solar particles increasing the amount of interplanetary scattering is not important.