U.S.-Japan Cooperative Research: Theoretical Investigations of Correlation in Few-Body Atomic Collisions

这一奖项将促进美国堪萨斯州立大学和阿贡国家实验室的物理学家与日本电子通信大学、筑波大学和京都大学之间的持续合作。科学家们正在合作研究重粒子碰撞和原子与反物质碰撞中的电子关联效应。当观察到的过程依赖于两个或多个电子之间的相互作用时，这些效应就会出现。与单电子过程相比，这种相互作用或相互依赖通常需要更复杂和更困难的处理。双电子过程的例子有双俘获、转移激发、转移电离、双电离和双激发。这些现象具有当前的实验意义，它们对理论家提出了新的挑战。美日合作科学计划下该项目的主要研究人员是堪萨斯州立大学的詹姆斯·H·麦奎尔博士和日本东京电子通信大学的松泽道夫博士。在当前的活动中，合作研究人员将在广泛的碰撞能量范围内研究质子和反质子对氦原子的双激发态和双电离的碰撞激发。他们还将研究库仑三体系统的某些方面，通过使用质量加权的超球坐标分析该系统的体-框架中的波函数。美国和日本的组织一直在调查类似的话题，之前也曾进行过合作。交换和组合方法和计算机代码应该证明对所涉及的每个小组以及对正在研究的物理过程的理解都是有益的。

This award will facilitate continued collaboration between physicists at Kansas State University and Argonne National Laboratory in the U.S. and the University of Electro- Communications, the University of Tsukuba, and Kyoto University in Japan. The scientists are cooperating in a study of what are known as electron correlation effects in heavy particle collisions and in collisions of atoms with antimatter. These effects arise when the processes being observed depend on the interaction between two or more electrons. Such interaction or interdependency in general requires a much more complicated and difficult treatment than when one-electron processes are considered. Examples of two-electron processes are double capture, transfer excitation, transfer ionization, double ionization, and double excitation. These phenomena are of current experimental interest, and they pose new challenges to theorists. The principal investigators in this project under the U.S.-Japan Cooperative Science Program are Dr. James H. McGuire, Kansas State University, and Dr. Michio Matsuzawa, The University of Electro-Communications, Tokyo, Japan. The collaborating researchers in this current activity will examine the impact excitation of doubly excited states and double ionization of helium atoms by protons and antiprotons over a wide range of collision energies. They will also study some aspects of Coulombic three-body systems by analyzing the wave functions in the body-frame of the system, using mass- weighted hyperspherical coordinates. The U.S. and Japanese groups have been investigating similar topics and have collaborated previously. Exchanging and combining methods and computer codes should prove beneficial to each group involved, and to the understanding of the physical processes being studied.