In section 9. The Sun
Magnetic flux emergence: a precursor of solar plasma expulsion
The emergence of magnetic flux through the stellar surface is a key to understanding the observable consequences of stellar activity on the surface and in the corona. The authors present a three-dimensional magneto-hydrodynamics models of this emergence process from the top of the convection zone into the lower corona. They find that the interaction of the emerging flux with the pre-existing field is crucial for the evolution of the eruption. For configurations favoring reconnection, ejective eruptions are found, while the emerging flux tube remains confined for other configurations.