title: Time-dependent resonant scattering: an analytical approach.
abstract: A time-dependent description is given of a scattering process involving a single resonance embedded in a set of flat continua. An analytical approach is presented which starts from an incident free particle wave packet and yields the Breit-Wigner cross-section formula at infinite times. We show that at intermediate times the so-called Wigner-Weisskopf approximation is equivalent to a scattering process involving a contact potential. Applications in cold-atom scattering and resonance enhanced desorption of molecules are discussed.
authors.affiliation: Laboratoire Aimé Cotton du CNRS, Ba^timent 505, Université de Paris-Sud, F-91405 Orsay, France.
authors.forename: J M
authors.initials: JM
authors.lastname: Lecomte
authors.forename: Adam
authors.initials: A
authors.lastname: Kirrander
authors.forename: Ch
authors.initials: Ch
authors.lastname: Jungen