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تسجيل مستخدم جديدDynamics of multi-cored magnetic structures in the quiet Sun
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We report on the dynamical interaction of quiet-Sun magnetic fields and granular convection in the solar photosphere as seen by textsc{Sunrise}. We use high spatial resolution (0farcs 15--0farcs 18) and temporal cadence (33 s) spectropolarimetric Imaging Magnetograph eXperiment data, together with simultaneous CN and Ca,textsc{ii},H filtergrams from textsc{Sunrise} Filter Imager. We apply the SIR inversion code to the polarimetric data in order to infer the line of sight velocity and vector magnetic field in the photosphere. The analysis reveals bundles of individual flux tubes evolving as a single entity during the entire 23 minute data set. The group shares a common canopy in the upper photospheric layers, while the individual tubes continually intensify, fragment and merge in the same way that chains of bright points in photometric observations have been reported to do. The evolution of the tube cores are driven by the local granular convection flows. They intensify when they are compressed by surrounding granules and split when they are squeezed between two moving granules. The resulting fragments are usually later regrouped in intergranular lanes by the granular flows. The continual intensification, fragmentation and coalescence of flux results in magnetic field oscillations of the global entity. From the observations we conclude that the magnetic field oscillations first reported by citet{2011ApJ...730L..37M} correspond to the forcing by granular motions and not to characteristic oscillatory modes of thin flux tubes.
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