We combine a convectively driven dynamo in a spherical shell with a nearlyisothermal density-stratified cooling layer that mimics some aspects of astellar corona to study the emergence and ejections of magnetic fieldstructures. This approach is an extension of earlier models, where forcedturbulence simulations were employed to generate magnetic fields. A sphericalwedge is used which consists of a convection zone and an extended coronalregion to $\approx1.5$ times the radius of the sphere. The wedge contains aquarter of the azimuthal extent of the sphere and $150\degr$ in latitude. Themagnetic field is self-consistently generated by the turbulent motions due toconvection beneath the surface. Magnetic fields are found to emerge at thesurface and are ejected to the coronal part of the domain. These ejectionsoccur at irregular intervals and are weaker than in earlier work. Wetentatively associate these events with coronal mass ejections on the Sun, eventhough our model of the solar atmosphere is rather simplistic.
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