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dc.contributor.advisorMcIntyre, Michael
dc.contributor.authorWood, Toby
dc.date.accessioned2011-02-14T12:19:59Z
dc.date.available2011-02-14T12:19:59Z
dc.date.issued2011-01-11
dc.identifier.urihttp://www.dspace.cam.ac.uk/handle/1810/230114
dc.identifier.urihttps://www.repository.cam.ac.uk/handle/1810/230114
dc.description.abstractIn this dissertation we consider the dynamics of the solar interior, with particular focus on angular momentum balance and magnetic field confinement within the tachocline. In Part I we review current knowledge of the Sun's rotation. We summarise the main mechanisms by which angular momentum is transported within the Sun, and discuss the difficulties in reconciling the observed uniform rotation of the radiative interior with purely hydrodynamical theories. Following Gough & McIntyre (1998) we conclude that a global-scale interior magnetic field provides the most plausible explanation for the observed uniform rotation, provided that it is confined within the tachocline. We discuss potential mechanisms for magnetic field confinement, assuming that the field has a roughly axial-dipolar structure. In particular, we argue that the field is confined, in high latitudes, by a laminar downwelling flow driven by turbulence in the tachocline and convection zone above. In Part II we describe how the magnetic confinement picture is affected by the presence of compositional stratification in the "helium settling layer" below the convection zone. We use scaling arguments to estimate the rate at which the settling layer forms, and verify our predictions with a simple numerical model. We discuss the implications for lithium depletion in the convection zone. In Part III we present numerical results showing how the Sun's interior magnetic field can be confined, in the polar regions, while maintaining uniform rotation within the radiative envelope. These results come from solving the full, nonlinear equations numerically. We also show how these results can be understood in terms of a reduced, analytical model that is asymptotically valid in the parameter regime of relevance to the solar tachocline. In Part IV we discuss how our high-latitude model can be extended to a global model of magnetic confinement within the tachocline.en_GB
dc.description.sponsorshipThis work was supported by a Research Studentship from the Science and Technology Facilities Councilen_GB
dc.language.isoenen_GB
dc.rightsAll Rights Reserveden
dc.rights.urihttps://www.rioxx.net/licenses/all-rights-reserved/en
dc.subjectHeliophysicsen_GB
dc.subjectSolar rotationen_GB
dc.subjectMagnetic fieldsen_GB
dc.subjectSolar tachoclineen_GB
dc.titleThe solar tachocline: a self-consistent model of magnetic confinementen_GB
dc.typeThesisen_GB
dc.type.qualificationlevelDoctoral
dc.type.qualificationnameDoctor of Philosophy (PhD)
dc.publisher.institutionUniversity of Cambridgeen_GB
dc.publisher.departmentDepartment of Applied Mathematics and Theoretical Physicsen_GB
dc.publisher.departmentQueens' Collegeen_GB
dc.identifier.doi10.17863/CAM.16099


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