Buoyant Magnetic Fields in the Sun

The subject of this project involves the physical processes governing the radial transport of magnetic fields in the solar interior. The interior of the Sun is generally divided into three main sections; the core (where energy is generated);the radiative zone and the convective zone so called because of the primary process by which heat is transferred. This project is concerned with the processes within the convective zone, where convection is the most signicant process of heat transport. It is believed that strong magnetic fields are generated at the base of the convective zone (or the tachocline). These magnetic fields "float" across the turbulent convective zone and appear at the surface (or photosphere) and are thought to be an important factor in the creation of sunspots, and coronal mass ejections. The project being undertaken here will look to better understand and model the process by which the magnetic fields move through the convective zone.

The primary process we are trying to understand is called magnetic buoyancy. Magnetic buoyancy relies on the convection of plasma within the Sun. To model convection and hence magnetic buoyancy we need a compressible model
which allows for changes in density since convection relies on fluid parcels being of different densities and "floating" accordingly. However, another feature of compressible fluids (fluids in which density perturbations exist) is sound or
acoustic waves. Sound waves are not of interest for this project because they are very computationally expensive to deal with. So one of the problems this project will seek to address is to find a model that can model magnetic buoyancy
without sound waves propagating - we call these models sound proof. Aims:
* To compare different sound proof models and assess how accurately they model magnetic buoyancy.
* Adapt an existing model or create a new model that models magnetic buoyancy in a way where sound waves are absent or of little consequence.
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