Self-consistent Simulations of Alfven Wave Driven Winds from the Sun and Stars

Abstract

We review our recent results of Alfven wave-driven winds. First, we present the result of a self-consistent 1D MHD simulations for solar winds from the photosphere to interplanetary region. Here, we emphasize the importance of the reflection of Alfven waves in the density stratified corona and solar winds. We also introduce the recent HINODE observation that might detect the reflection signature of transverse (Alfvenic) waves by Fujimura & Tsuneta (2009). Then, we show the results of Alfven wave-driven winds from red giant stars. We explain the change of the atmosphere properties from steady coronal winds to intermittent chromospheric winds and discuss how the wave reflection is affected by the decrease of the surface gravity with stellar evolution. We also discuss similarities and differences of accretion disk winds by MHD turbulence.