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arXiv · 1506.01193

Locally Supported Wavelets for the Separation of Spherical Vector Fields with Respect to their Sources

Christian Gerhards
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Abstract

We provide a space domain oriented separation of magnetic fields into parts generated by sources in the exterior and sources in the interior of a given sphere. The separation itself is well-known in geomagnetic modeling, usually in terms of a spherical harmonic analysis or a wavelet analysis that is spherical harmonic based. In contrast to these frequency oriented methods, we use a more spatially oriented approach in this paper. We derive integral representations with explicitly known convolution kernels. Regularizing these singular kernels allows a multiscale representation of the internal and external contributions to the magnetic field with locally supported wavelets. This representation is applied to a set of CHAMP data for crustal field modeling.

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Christian Gerhards. 2015-06-03. Locally Supported Wavelets for the Separation of Spherical Vector Fields with Respect to their Sources. https://arxiv.org/abs/1506.01193

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