Second term of the asymptotic expansion of the diffracted wave in the shadow

Abstract

In this paper we calculate the second order term of the Neumann operator for the high frequency scattering of a wave by a strictly convex obstacle Ω using the techniques introduced by G. Lebeau and used in previous works. This second term is used to calculate the scattering by Ω⊂R², and the result is compared to previous results of V. Babich and I. Molotkov. We generalize the calculation when Ω⊂R³.