About features of ion’s energy spectra variations in cosmic ray fluxes from solar flares
The most powerful phenomena of solar energetic particles are known to occur as a result of joint action of particle acceleration mechanisms in the process of magnetic field reconnection in the solar flares and on the fronts of shock waves generated by moving coronal mass ejections (CME) in the corona and interplanetary medium which are related with flares. The behavior of energy spectra of particle streams accelerated by two main mechanisms contains important information about particle acceleration and their propagation in the interplanetary medium to the Earth. The preliminary results have shown that CME shock fronts have a significant impact on the spectral structure of the accelerated particle fluxes in the relatively rare cases when there are enhanced proton fluxes with energies of greater than 60 MeV with intensity higher than 102 p/(cm2∙sec∙sr), accelerated by shock waves. At the same time the sharp breaks of ion spectra in the energy range of 1.5−2.5 MeV are observed. We considered three such cases (July 14−15, 2000; September 24−25, 2001; November 8−10, 2000). Ion energy spectra of H, He, O and Fe before and after the arrival of the shock wave were given to determine the degree of the shock wave influence on the structure and elemental composition of the ion fluxes for these events of solar cosmic rays (SPE) on measurements from spacecrafts. The possible causes of sharp changes in the character of the ion spectra in this energy range were analyzed. We present a qualitative explanation of variations in the ratio Fe/O in these solar events based on the FIP effect.
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