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تسجيل مستخدم جديدObservation of solar coronal heating powered by magneto-acoustic oscillations in a moss region
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In this paper, we report the observed temporal correlation between extreme-violet (EUV) emission and magneto-acoustic oscillations in a EUV moss region, which is the footpoint region only connected by magnetic loops with million-degree plasma. The result is obtained from a detailed multi-wavelength data analysis to the region with the purpose of resolving fine-scale mass and energy flows that come from the photosphere, pass through the chromosphere and finally heat solar transition region or the corona. The data set covers three atmospheric levels on the Sun, consisting of high-resolution broad-band imaging at TiO 7057 AA and the line of sight magnetograms for the photosphere, high-resolution narrow-band images at Helium textsc{i} 10830 AA for the chromosphere and EUV images at 171 AA for the corona. We report following new phenomena: 1) Repeated injections of chromospheric material shown as 10830 AA absorption are squirted out from inter-granular lanes with the period of $sim$ 5 minutes. 2) EUV emissions are found to be periodically modulated with the similar periods of $sim$ 5 minutes. 3) Around the injection area where 10830 AA absorption is enhanced, both EUV emissions and the strength of magnetic field are remarkably stronger. 4) The peaks on the time profile of the EUV emissions are found to be in sync with oscillatory peaks of the stronger magnetic field in the region. These findings may give a series of strong evidences supporting the scenario that coronal heating is powered by magneto-acoustic waves.
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