THE HEATING OF SOLAR WIND PROTONS THROUGH ENERGY CASCADE OF ALFVENIC FLUCTUATIONS

The observations by Helios 1 and 2 spacecrafts showed that with increasing hiliocentric distance the proton magnetic moment and the proton’s second invariant decreases. This phenomena indicates that some heating is required for the proton perpendicular temperature while some cooling process is required for the proton parallel temperature. No theory which is consistent with observations has been pubished to explain the phenomena. Based on Alfvenic fluctuation’s model of Tu 1988 and the quasi-linear theory of proton-cyclotron resonance, a model which can describe the inversion of the energy cascade of Alfvenic flucturations to the heat of protons and the inversion of the parallel energy to the perpendicular energy is developed. This model can explain the perpendicular heating and parallel cooling of the protons in the solar wind.