On scattering of $H$-polarized electromagnetic field by ideal conductive cylinder with narrow lengthwise split of finite depth

The Neumann boundary value problem on plane associated with scattering of $H$-polarized electromagnetic field by ideal conductive cylinder with a narrow lengthwise split of finite depth was considered. Asymptotics respect with to a small parameter (width of split) of solution poles with a small imaginary part was constructed. It has shown that these poles have resonant nature. Bibliography: 5 titles.