MPS-Ascend: Observation of the Positronium Plus Ion and Development of a Spin-Polarized Positron Beam for Angle-Resolved Positronium Emission Spectroscopy

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。Gabriel Cecchini被授予NSF数学和物理科学提升博士后研究奖学金，以开展与扩大STEM中代表性不足的群体参与相关的研究和活动项目。Cecchini博士的研究项目名为“MPS-Ascend：正电子+离子的观察和角分辨正电子发射光谱的自旋极化正电子束的开发”，由一位赞助科学家指导。该奖学金的主办机构是加州大学河滨分校（UCR），赞助科学家是艾伦·米尔斯博士。切奇尼将进行一项研究项目，首次创造和观察正电子离子（Ps+）。这种离子的存在最初是在1946年预测到的，至今还没有在实验室中观察到。Ps+作为一种纯轻子系统，可以用于量子电动力学（QED）的测试。此外，对正电子源的改进将使一种新的角度分辨正电子发射光谱仪（arpse）得以开发。切奇尼将在UCR的正电子实验室指导学生，UCR既是一个拉美裔服务机构，也是一个亚裔美国人、美洲原住民和太平洋岛民服务机构。他将与当地的高中教师和学生一起工作，并将参加会议和援助计划，旨在招募，保留和毕业传统上在STEM中代表性不足的团体成员，如美国科学促进会（AAAS），研究生教育和教授联盟（AGEP），以及包容性研究生教育网络（IGEN）。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Gabriel Cecchini is awarded an NSF Mathematical and Physical Sciences Ascending Postdoctoral Research Fellowship to conduct a program of research and activities related to broadening participation by groups underrepresented in STEM. This fellowship to Dr. Cecchini supports his research project entitled "MPS-Ascend: Observation of the Positronium Plus Ion and Development of a Spin-Polarized Positron Beam for Angle-Resolved Positronium Emission Spectroscopy", under the mentorship of a sponsoring scientist. The host institution for the fellowship is the University of California Riverside (UCR) and the sponsoring scientist is Dr. Allen Mills.Cecchini will pursue a research project to create and observe, for the first time, the positronium plus ion (Ps+). The existence of this ion was originally predicted in 1946 and has yet to be observed in the laboratory. As a pure lepton system, Ps+ could be used in tests of quantum electrodynamics (QED). In addition, improvements in the positron source will enable the development of a new angle-resolved positronium emission spectrometer (ARPsES). Cecchini will mentor students in the positron lab at UCR, which is both a Hispanic Serving Institution and an Asian American, Native American, and Pacific Islanders Serving Institution. He will work with local high school teachers and students and will participate in conferences and assistance programs geared to recruitment, retention, and graduation of members of groups traditionally underrepresented in STEM such as the American Association for the Advancement of Science (AAAS), the Alliance for Graduate Education and the Professoriate (AGEP), and the Inclusive Graduate Education Network (IGEN).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.