Analytical modelling of multi-spacecraft reconnection layer measurements at the magnetopause

Crofts, Jonathan Daniel (2011) Analytical modelling of multi-spacecraft reconnection layer measurements at the magnetopause. Doctoral thesis (DPhil), University of Sussex.

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Abstract

An approach to determine and analyse the structure of Petschek-type magnetic
reconnection is developed. This is achieved by extending an analytical model based
on the Rankine-Hugoniot wave equation for shock jump conditions and is described
in terms of its past applications and limitations. The model is applied to data
from the CLUSTER multi-spacecraft mission using a boundary condition method
optimised by two interlinked genetic algorithms.
Case studies for a range of locations within the magnetopause region and local conditions are described and subjected to fluid and particle analyses to confirm the presence of reconnective signatures. Genetic algorithms are used to optimise the fit of the model, by modifying the boundary condition selection and internal structure parameters. This information then facilitates the construction of a more accurate modelled layer structure for each event. The calculated values for state variables within these layers are compared quantitatively and qualitatively to the magnetopause boundary crossings present in the CLUSTER data. Case study results are summarised and compared before being compiled into quantitative statistics for describing the local and possibly global applicability of the model. The fast application of these methods by means of an automatic process to a large set of data is described, as are the wider possibilities arising from this and the limitations of model, methods and data. These results are used to support several assertions. Firstly, that this model is indeed applicable, within its limitations, to the study of reconnection events within the magnetospheric environment. It can also facilitate deeper studies of individual reconnection events, in addition to being employed as a basis to classify wider statistical trends in spatio-temporal structures.

Item Type: Thesis (Doctoral)
Schools and Departments: School of Engineering and Informatics > Informatics
Subjects: Q Science > QB Astronomy > QB0460 Astrophysics
Q Science > QC Physics
Depositing User: Library Cataloguing
Date Deposited: 03 May 2011 06:27
Last Modified: 14 Aug 2015 11:52
URI: http://sro.sussex.ac.uk/id/eprint/6338

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