title: Identification of the radiative and nonradiative parts of a wave field.
abstract: We present a method for decomposing a wave field, described by a second-order ordinary differential equation, into a radiative component and a nonradiative one, using a biorthonormal system related to the problem under consideration. We show that it is possible to select a special system such that the wave field is purely radiating. We discuss the differences and analogies with approaches which, unlike our approach, start from the corresponding sources of the field.
authors.affiliation: Institute for Theoretical Physics, University of Groningen, The Netherlands. b.j.hoenders@phys.rug.nl
authors.forename: B J
authors.initials: BJ
authors.lastname: Hoenders
authors.forename: H A
authors.initials: HA
authors.lastname: Ferwerda