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Magnetic and thermal structuring and dynamics of solar coronal active regions

This thesis is a study of the magnetic and thermal structuring and dynamics of the solar corona. The work presented here is primarily split into two sections: Initially a study of sausage oscillations of coronal structures in two geometries. Then the development of a static model of a coronal active region. Initially the basic concepts involved in studying the solar corona, in particular those relevant to this thesis, are introduced and explained. In the second chapter sausage mode oscillations in a cylindrical geometry are studied in more detail. In particular a model of these oscillations is developed and used to study the behaviour of these oscillations over a wide range of wavelengths. The use of a wide range of wavelengths allows the resolution of a long-standing disagreement between results found in the long and short wavelength regions. The results of the model developed in chapter 2 are then compared with a novel analytical expansion of the dispersion relation. In chapter 3 the study is extended to the slab geometry, and this is compared to the results found in the cylindrical geometry. The second section of work begins in chapter 4, we develop amodel of a static active region, from magnetogram data taken by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory (SDO/HMI). This was done using a NLFF magnetic field extrapolation, and a 1-D hydrostatic model. The initial results of this modelling are also compared to EUV observations of these active regions. In chapter 5 the results and behaviour of this model is explored in more detail. In particular the behaviour of the hydrostatic model with a varying heating rate. Several individual loops are considered from the magnetic field model and studied in more depth. Various potential diagnostics for the coronal heating function are also considered.

Identiferoai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:690479
Date January 2015
CreatorsHornsey, Chris
PublisherUniversity of Warwick
Source SetsEthos UK
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Sourcehttp://wrap.warwick.ac.uk/80137/

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