Theoretical Study of Few-Body Processes

少体过程的理论研究

• 批准号: 0456528
• 负责人: Don Madison
• 金额: $ 27万
• 依托单位: Missouri University of Science and Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0456528&HistoricalAwards=false
• 关键词: Theoretical; Study; Few; Body; Processes

Collision physics is entering an incredibly exciting time as a result of recent new experimental advances. One of these advances is the COLTRIMS (cold-target recoil-ion momentum spectroscopy) method. With this method, one can obtain full three-dimensional absolute cross sections for ionization of atoms and molecules by an arbitrarily charged particle. The most detailed information is contained in the fully differential cross section (FDCS) measurements in which the energy and angular location of all the final state particles are measured. Prior to COLTRIMS, FDCS measurements were made only for electron impact, normally only in the scattering plane, and the data were typically not absolute. With COLTRIMS, FDCS measurements are possible for any particle, any anti-particle, or arbitrarily charged ion. Now that these data are available to be compared with theory, there are surprises; the best theories are not in agreement with the experimental data.This research will investigate these open theoretical questions using a variety of different theoretical approaches ranging from first-order perturbation theory using the most accurate possible initial- and final state wavefunctions, to second-order distorted-wave approaches, to many-body perturbation theory. It is anticipated that different approaches will provide different insights into the physics of the collisions.

碰撞物理学正进入一个令人难以置信的激动人心的时刻，由于最近的新实验进展。其中一项进展是COLTRIMS（冷靶反冲离子动量谱）方法。用这种方法可以得到任意带电粒子电离原子和分子的全三维绝对截面。最详细的信息包含在全微分截面（FDCS）测量中，其中测量所有终态粒子的能量和角位置。在COLTRIMS之前，FDCS测量仅针对电子碰撞，通常仅在散射平面中进行，并且数据通常不是绝对的。使用COLTRIMS，FDCS测量可以用于任何粒子，任何反粒子或任意带电离子。 现在这些数据可以与理论进行比较，有惊喜;最好的理论与实验数据不一致。本研究将使用各种不同的理论方法来研究这些开放的理论问题，从一阶微扰理论，使用最精确的初态和终态波函数，到二阶扭曲波方法，到多体微扰理论。 预计不同的方法将为碰撞的物理学提供不同的见解。