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On the Role of Acoustic-gravity Waves in the Energetics of the Solar Atmosphere

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 نشر من قبل Thomas Straus
 تاريخ النشر 2010
  مجال البحث فيزياء
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In a recent paper (Straus et al. 2008) we determined the energy flux of internal gravity waves in the lower solar atmosphere using a combination of 3D numerical simulations and observations obtained with the IBIS instrument operated at the Dunn Solar Telescope and the Michelson Doppler Imager (MDI) on SOHO. In this paper we extend these studies using coordinated observations from SOT/NFI and SOT/SP on Hinode and MDI. The new measurements confirm that gravity waves are the dominant phenomenon in the quiet middle/upper photosphere and that they transport more mechanical energy than the high-frequency (> 5mHz) acoustic waves, even though we find an acoustic flux 3-5 times larger than the upper limit estimate of Fossum & Carlsson (2005). It therefore appears justified to reconsider the significance of (non-M)HD waves for the energy balance of the solar chromosphere.



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