Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul


Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul
(A multiwavelength model to visualise and analyse magnetic fields in the solar corona)

Jeff Smith

The Sun is a dynamic, complex system, full of interesting and important features. These kinds of features can be modeled in various ways, such as with Non-Linear Force-Free Field (NLFFF) models. In this paper, NLFFF simulations are built. The intention is to estimate spatial patterns of the magnetic field in the solar chromosphere and corona and changes in the free energy in the system, in particular losses of energy as a result of solar eruptions. Most existing models have a temporal cadence of 12 minutes at best (that is, the situation is simulated every 12 minutes). The method discussed in this paper makes various approximations but it aims to achieve a temporal cadence of 45 seconds. The method used is found to successfully simulate synthetic data, and when dealing with real data, it produces images which frequently correspond well to observations. Several reductions in the free energy of the system are seen, corresponding to observed eruptions.


Reference:

 
  	Jeff Smith, 'Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul', Gwerddon, 18, September 2014, 23-40.
   

Keywords

 
    Sun, NLFFF, corona loops, simulate, eruptions, oscillations, energy.
    

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