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arXiv · 1210.3194

A note on analyticity properties of far field patterns

Abstract

In scattering theory the far field pattern describes the directional dependence of a time-harmonic wave scattered by an obstacle or inhomogeneous medium, when observed sufficiently far away from these objects. Considering plane wave excitations, the far field pattern can be written as a function of two variables, namely the direction of propagation of the incident plane wave and the observation direction, and it is well-known to be separately real analytic with respect to each of them. We show that the far field pattern is in fact a jointly real analytic function of these two variables.

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Roland Griesmaier, Nuutti Hyvönen, Otto Seiskari. 2012-10-11. A note on analyticity properties of far field patterns. https://arxiv.org/abs/1210.3194

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