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Supersonic Magnetic Upflows in Granular Cells Observed with Sunrise/IMaX

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 نشر من قبل Juan Manuel Borrero
 تاريخ النشر 2010
  مجال البحث فيزياء
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Using the IMaX instrument on-board the Sunrise stratospheric balloon-telescope we have detected extremely shifted polarization signals around the Fe I 5250.217 {AA} spectral line within granules in the solar photosphere. We interpret the velocities associated with these events as corresponding to supersonic and magnetic upflows. In addition, they are also related to the appearance of opposite polarities and highly inclined magnetic fields. This suggests that they are produced by the reconnection of emerging magnetic loops through granular upflows. The events occupy an average area of 0.046 arcsec$^2$ and last for about 80 seconds, with larger events having longer lifetimes. These supersonic events occur at a rate of $1.3times10^{-5}$ occurrences per second per arcsec$^{2}$.



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