Inevitable consequences of ion-neutral damping of intermediate MHD waves in Sun-like stars

We solve conservation equations for the hydrodynamics and for hydrogen and helium ionization stages, along closed tubes of magnetic field. First, we examine the evolution of coronal plasma under conditions where coronal heating has abruptly ceased.

We find that cool ( 10(4)) K long (> several Mm) tubes of plasma arise by the same mechanism. We speculate on the relevance of these solutions to observe properties of the Sun and similar stars whose atmospheres are permeated with emerging magnetic fields and stirred by convection. Perhaps this elementary process might help to explain the presence of 'cool loops' in the solar transition region and the production of broad components of transition region lines.