Topology of forward scattering of neutrons from imperfect multilayers

Neutrons sent at grazing incidence on imperfect multilayers of polymers are scattered both out of and within the plane of reflection. In the latter geometry the scattered intensity is highly structured in two series of ridges, whose loci can be labeled in terms of the neutron momenta. Intersecting ridges show evidence of mode coupling. Similar topology is expected for x-ray scattering. © 1994 The American Physical Society.