RELATION OF THE CHROMOSPHERIC NETWORK TO CORONAL FUNNELS AND THE SOLAR WIND

摘要

We investigate the plasma flow out of a coronal funnel in the framework of a forward 2D MHD model including the calculation of EUV emission lines. The computational box stretches from the chromosphere into the corona and special attention is paid to the relation of the magnetic structure at the base of the funnel to the wind outflow at its top. We use parameterized heating functions, e.g. depending on the magnetic field strength, to keep a corona and drive the wind. When observing the funnel from straight above, the highest Doppler (blue) shifts synthesized from our model are found above the edges of the magnetic field concentrations in the chromosphere for some heating functions. The same holds for the intensities of coronal emission lines. Furthermore we find that the signature of the magnetic field concentration at the base of the funnel is still to be found in the high corona in the density and temperature structure, and thus in emissivity and Doppler shift, while the magnetic field is (almost) homogeneous. This shows that signatures found in the solar wind (at 0.3 to 1 AU) on an angular scale comparable to the super-granular network of the Sun might indeed be a signature of the chromospheric magnetic network.