SOURCE MATERIAL OF SOLAR ENERGETIC PARTICLES FROM THE HIGH CHROMOSPHERE AND OVERA- BUNDANCE OF HEAVY IONS BY THE FORCE- FREE FIELD OF SUNSPOTS

This paper presents a new idea by modelling the high chromosphere of source material of solar energetic particles. Based on the temperature as determined by the data of overabundance of heavy ions relative to local galactic abundances in solar energetic particle events, the high chromosphere is suggested to be the source of solar energetic particles. According to a great number of observations, the acceleration region of solar energetic particles during solar flares is most likely to occur in the low corona and even up to tens thousand kilometres height. Therefore, the source region of solar cosmic rays is generally not so same as that of the particle acceleration. Moreover, the author presents further a model of mechanism of overabundance of heavy ions in solar energetic particle events. From the model, the heavy nuclei with low first-ionization potentials in the source are preferentially affected by electromagnetic force of force-free field in the frozen magnetic field of sunspot and are transported to sunspot region by this action, their abundances are larger in the acceleration region before the onset of solar flares and are overabundant in solar cosmic rays.