The effects of Alfven waves and radiation pressure in dust winds of late-type stars

In the present study, we analyze the effects of a flux of Alfven waves acting together with radiation pressure on grains as an acceleration mechanism of the wind of late-type stars. In the wind model, we simulate the presence of grains through a strong damping of the waves, and we use a nonisothermal pro le for the temperature that is coherent with grain formation theories. We examine the changes in the velocity pro le of the wind, and we show that if the grains are created in the region 1.1 < r/r(0) < 2.0, their presence will affect the mass loss and terminal velocity. The model is applied to a K5 supergiant star and to Betelgeuse (alpha Ori).