U.S.-France Cooperative Research: Dynamics of Ultracold Collisions

该奖项将支持物理学方面的合作研究 马里兰州大学的约翰·韦纳博士和 Francoise Masnou-Seeuws，原子和分子实验室 碰撞，奥赛，法国。 调查人员提出了一个 合作计划，其中实验（在美国方面）和 理论（在法国方面）将联合收割机，以推进理解- 超冷碰撞动力学的研究 流程. 韦纳博士和他的研究小组目前正在进行 碱金属缔合电离碰撞实验 原子束 他们测量了 概率是碰撞速度的函数，激发- 所述对准和取向以及光场强度 在碰撞温度范围内， 温度降到1 mK以下。 这些结果必须是 解释为非常长的行为， 几种核间分离的电势曲线 一百到一千多个原子单位。 此外，委员会认为， 非弹性碰撞的紧密耦合理论是不必要的， 可以适当地描述散射事件。 博士 Masnous-Seeuws是这些领域公认的世界权威， 和她在奥赛的理论小组，将运用他们的专业知识， 对实验结果的彻底解释 这一共同努力将使人们清楚地了解 超冷温度下的化学键形成机制。

This award will support collaborative research in physics between Dr. John Weiner, University of Maryland, and Dr. Francoise Masnou-Seeuws, Laboratory for Atomic and Molecular Collisions, Orsay, France. The investigators propose a cooperative program in which experiments (on the US side) and theory (on the French side) will combine to advance understand- ing of the dynamics of ultracold collisions in elementary processes. Dr. Weiner and his research group are currently carrying out experiments on associative ionization collisions in alkali atomic beams. They have performed measurements of reaction probability as a function of collision velocity, excited- state alignment and orientation, and optical-field intensity over collision temperatures, ranging from several hundred degrees Kdown to less than 1 mK. These results must be interpreted in terms of the very long-range behavior of potential curves at internuclear separations from several hundred to more than a thousand atomic units. Furthermore, close coupling theories of inelastic collisions are indispen- sible to a proper description of the scattering event. Dr. Masnous-Seeuws, a recognized world authority in these areas, and her theory group at Orsay, will apply their expertise to a thoroughgoing interprestation of the experimental results. The combined effort will lead to a clear understanding of chemical bond-forming mechanisms at ultracold temperatures.