We have carried out numerical experiments of the emergence of magnetic flux from the solar interior into the corona for the case when the latter has a preexisting, large-scale magnetic field. The emergence into the lower atmosphere basically follows the same patterns as when the corona is unmagnetized. Yet, upon contact of the upcoming magnetized plasma with the corona, the following processes are observed to take place: formation of a concentrated, arch-shaped current sheet; reconnection between the field lines of the corona and of the upcoming plasma system; heating to high temperatures in the reconnection sites; launching of high-velocity outflows. Those features have been described in a recent paper (Galsgaard et al, 2004), including the (crucial) dependence on the mutual orientation of the magnetic field in the two systems. The present contribution provides complementary illustration of various aspects of the problem.
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