A uniqueness theorem for an inverse scattering problem in an exterior domain
A uniqueness theorem for an inverse scattering problem in an exterior domain
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DOI:
10.1137/s0036141097318614
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发表时间:
1998-09
影响因子:
2
通讯作者:
P. Hähner
中科院分区:
文献类型:
--
作者:
P. Hähner
The scattering of time-harmonic acoustic waves by a simply connected, sound-soft obstacle in an inhomogeneous medium in R2 is considered. We prove that the Cauchy data of the scattered waves on a large circle for all incident waves and for an interval of wave numbers $\kappa$ uniquely determine the obstacle and the inhomogeneity. To this end we show that products of harmonic functions satisfying a Dirichlet condition on the interior boundary of an annular plane domain are complete. Then, we use the limit $\kappa \to 0$ and obtain uniqueness of the obstacle from Schiffer's uniqueness result. Uniqueness of the inhomogeneity also follows from $\kappa \to 0$ together with the denseness result for the linear span of products of harmonic functions.