title: Exterior caustics produced in scattering of a diagonally incident plane wave by a circular cylinder: semiclassical scattering theory analysis.
abstract: We use the semiclassical limit of electromagnetic wave scattering theory to determine the properties of the exterior caustics of a diagonally incident plane wave scattered by an infinitely long homogeneous dielectric circular cylinder in both the near zone and the far zone. The transmission caustic has an exterior/interior cusp transition as the tilt angle of the incident beam is increased, and each of the rainbow caustics has a farzone rainbow/exterior cusp transition and an exterior/interior cusp transition as the incident beam tilt angle is increased. We experimentally observe and analyze both transitions of the first-order rainbow. We also compare the predictions of the semiclassical approximation with those of ray theory and exact electromagnetic wave scattering theory.
authors.affiliation: Department of Physics, Cleveland State University, Ohio 44115, USA. jimandcarol@stratos.net
authors.forename: J A
authors.initials: JA
authors.lastname: Lock
authors.forename: C L
authors.initials: CL
authors.lastname: Adler
authors.forename: E A
authors.initials: EA
authors.lastname: Hovenac