Relevance of magnetic flux expulsion from the lower solar atmosphere to the acceleration of the solar wind

The authors show that the ultimate fate of a diamagnetic body as it moves outward into the corona due to forces exerted by the external field is critically dependent upon how important the internal gas pressure is relative to the internal magnetic pressure. If the pressure is identically zero, the body will expand self-similarly for all time if dissipative processes do not occur. If the internal β is non-zero, however, it will ultimately deform into a jet since the magnetic energy continually declines in the authors' model whereas the thermal energy does not. This conclusion, however, rests upon their assumption that the temperature of the body remains isothermal. It it declines as expected, the result could be quite different. Future work will remove the restriction of isothermality. Also, hydrodynamic effects could also change the picture considerably. Such effects are currently under consideration