RUI: Low Energy Positronium Interactions with Atoms and Molecules in a Gas Environment

RUI：气体环境中低能正电子与原子和分子的相互作用

• 批准号: 0555631
• 负责人: Jason Engbrecht
• 金额: --
• 依托单位: Saint Olaf College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0555631&HistoricalAwards=false
• 关键词: RUI; Low; Energy; Positronium; Interactions

This experimental research program focuses on the understand of basic interactions between positronium (a system with one electron and one positron bound together) and atoms and/or molecules in a gas environment. At the heart of this research is a newly developed Age-Momentum Correlation apparatus designed to observe positronium formed. This apparatus has already enabled the first quantitative observation of positronium at thermal energies with a High-Purity Germenium (HPGe) detector, demonstrating an unprecedented precision and range for the technique. With the power of the technique firmly established, measurements of the momentum-transfer cross-section for positronium scattering off atoms and/or molecules will be measured in a wider variety of gases, over a broader energy range (below 6.8 electron volts), and with greater precision than any previous experiment. Furthermore, it will be directly sensitive to pick-off annihilation (the decay of the electron and positron into gamma rays) in a new and more direct way, allowing new insights into this process. The broader impact of the program involves undergraduate student education as well as applications to biological systems.

这项实验研究计划侧重于了解正电子(一个电子和一个正电子结合在一起的系统)与气体环境中的原子和/或分子之间的基本相互作用。这项研究的核心是一种新开发的年龄-动量关联设备，旨在观察正电子的形成。该装置已经实现了用高纯锗(HPGe)探测器在热能下对正电子进行第一次定量观测，展示了该技术前所未有的精度和范围。有了这项技术的强大力量，正电子对原子和/或分子散射的动量转移截面的测量将在更广泛的气体中测量，在更宽的能量范围内(低于6.8电子伏)，并且比以前的任何实验都更精确。此外，它将以一种新的、更直接的方式对拾取湮灭(电子和正电子衰变为伽马射线)直接敏感，从而允许对这一过程的新见解。该项目的更广泛影响涉及本科生教育以及生物系统的应用。