Effect of electron resonant heating on the kinetic evolution and acceleration of the solar wind

We investigate the effects of electron cyclotron resonant heating on the kinetic evolution and acceleration of the fast solar wind. A previous study has shown that kinetic wave-particle interactions due to ion resonant heating, may account for the bulk acceleration of the solar wind, the preferential heating of the helium ions over the protons, as well as the occasionally observed double-peaked proton velocity distributions. The model followed the evolution of the particle distributions along an inhomogeneous field line under the effects of ion heating, Coulomb collisions, and an ambipolar electric field that was consistent with the distributions themselves. This study extends the model to take into account also the effect of electron cyclotron resonant heating. Our parametric study shows that the electron heating does not change the solar wind qualitative features described above. However, the wave-particle interaction increases the ambipolar electric field, thereby enhancing the solar wind velocity.