Coupling effects throughout the solar atmosphere: Emerging magnetic flux and structure formation

摘要

We report observations of the “birth,” formation, and evolution of compact coronal structures associated with strong localized motions generated by emerging magnetic flux in the photosphere. We use multiwavelength time series of data taken simultaneously with the Swedish Vacuum Solar Telescope (SVST) on La Palma, the TRACE satellite, and the MDI instrument on SOHO. We find that long before the magnetic pore is formed, the chromosphere and transition region show a high activity above the future site of pore formation: rising but not yet visible magnetic flux exerts a strong pressure on the overlying plasma generating highly collimated plasma flows seen in the Hα images. About the time when the magnetic pores are formed and the Hα surges bifurcate into the established arc-like flows, a system of compact coronal loops is formed, showing direct connection between the motions associated with the evolving magnetic fields and the coronal structure formation. We propose a mechanism that may lead to the observed phenomena based on the generation of currents by strong disturbances propagating upward from a limited surface area.