title: Observation of a motional Stark effect to determine the second-order Doppler effect.
abstract: The high resolution two-photon spectroscopy of hydrogen is often limited by the second-order Doppler effect. To determine this effect, we apply a magnetic field perpendicular to the atomic beam. This field induces a quadratic motional Stark shift proportional, as the second-order Doppler effect, to v(2) (v atomic velocity). For some magnetic field, these two effects are opposite and the total shift due to the atomic velocity is reduced. We present the first observation of this effect for the 1S-3S transition in hydrogen.
authors.affiliation: Laboratoire Kastler Brossel, Département de Physique de l'Ecole Normale Supérieure, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05, France.
authors.forename: G
authors.initials: G
authors.lastname: Hagel
authors.forename: R
authors.initials: R
authors.lastname: Battesti
authors.forename: F
authors.initials: F
authors.lastname: Nez
authors.forename: L
authors.initials: L
authors.lastname: Julien
authors.forename: F
authors.initials: F
authors.lastname: Biraben