PROPAGATION EFFECTS OF SOLAR COSMIC RAYS (II)——PROPAGATION CORRECTION OF PEAK SPECTRUM

The influence of interplaneatry propagation upon the peak spectrum of the solar cosmic say events are discussed in terms of the dimensional solution for the propagation equation with emphasis on the importance of the propagation correction of spectrum.Solar wind convection is one of the probable causes of flattening in low energy spectrum.Under certain conditions, an injected power-law spectrum may change into an observed exponential one, and a kinetic energy spectrum into a rigidity one.The power index of spectrum increases with the magnetic azimuth of source flares, the distribution of which shows a marked east-west asymmetry.Furthermore, the injection spectrum of the relativistic events observed during the 20th solar cycle are evaluated through a correction for the propagation effect, some of the deduced injection spectra may be expressed as a power law with a unitary index, while others are still flattened in the low energy range.