For a bounded open domain $\Omega\subset\mathbb R^2$ with connected complement and piecewise smooth boundary, we consider the Dirichlet Laplacian $\Delta$ on $\Omega$ and the S-matrix on its complement. We obtain precise bounds on the total scattering phase and and a Krein spectral formula, which improve similar results found in the literature
@article{hal-00129119,
author = {Pillet, Claude-Alain and Eckmann, Jean-Pierre},
title = {Scattering phases and density of states for exterior domains},
journal = {HAL},
volume = {1995},
number = {0},
year = {1995},
language = {en},
url = {http://dml.mathdoc.fr/item/hal-00129119}
}
Pillet, Claude-Alain; Eckmann, Jean-Pierre. Scattering phases and density of states for exterior domains. HAL, Tome 1995 (1995) no. 0, . http://gdmltest.u-ga.fr/item/hal-00129119/