title: Extinction and the optical theorem. Part I. Single particles.
abstract: We study the extinction caused by a single particle and present a conceptual phase-based explanation for the related optical theorem. Simulations of the energy flow caused by a particle's presence in a collimated beam of light demonstrate how the extinction process occurs. It is shown that extinction does not necessarily cause a reduction of the energy flow along the exact forward direction. Implications regarding the measurement of the single-particle extinction cross section are discussed. This work is extended to noninteracting and interacting multiparticle groups in Part II [J. Opt. Soc. Am. A25, pp. 1514 (2008)].
authors.affiliation: Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Berg
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Sorensen
authors.forename: Amitabha
authors.initials: A
authors.lastname: Chakrabarti