Distribution of resonances in scattering by thin barriers

The author studies high energy resonances for the operators -\Delta_{\partial\Omega,\delta}:=-\Delta +\delta_{\partial\Omega}\otimes V\quad \textrm{and}\quad -\Delta_{\partial\Omega,\delta'}:=-\Delta+\delta_{\partial\Omega}'\otimes V\partial_\nu where \Omega\subset{\mathbb{R}}^{d} is strictly convex with smooth boundary, V:L^{2}(\partial\Omega)\to L^{2}(\partial\Omega) may depend on frequency, and \delta_{\partial\Omega} is the surface measure on \partial\Omega.