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16/07/2008, 15:00 — 16:00 — Room P3.10, Mathematics Building

David Colton, *Universidade de Delaware*

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The inverse scattering problem for an obstacle

This talk is designed to be an introduction to inverse scattering theory for the non expert, focusing on the inverse electromagnetic scattering problem for a perfect conductor. We begin by considering scattering by an infinite cylinder in which case the governing equation is the two dimensional Helmholtz equation. After considering uniqueness questions for the inverse problem, we proceed to describing the three main methods for solving the inverse problem: the method of physical optics, Newton's method and the linear sampling method. We conclude by considering the three dimensional inverse scattering problem, focusing on the linear sampling method for Maxwell's equations. Numerical examples will be given using both real and synthetic scattering data.