RUI: Models of Hadron Structure and Interactions

RUI：强子结构和相互作用模型

• 批准号: 0855656
• 负责人: Mary Alberg
• 金额: $ 14.87万
• 依托单位: Seattle University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0855656&HistoricalAwards=false
• 关键词: RUI; Models; Hadron; Structure; Interactions

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).In this project we study two topics in theoretical nuclear physics related to the structure of hadrons (e.g. protons, neutrons and their antiparticles) and to their interactions. The first topic is the fundamental question of how the properties of a hadron (e.g. momentum and spin) are distributed among its constituent partons: quarks, antiquarks and gluons. Two theoretical frameworks will be used. In the first, a hadron fluctuates into meson-baryon pairs, and the hadron's parton distribution is determined by the parton distributions of the mesons and baryons in the fluctuations. In the second, the hadron's parton distributions are calculated in a statistical model. This study will address one of the outstanding challenges to theory posed by recent experiment, the momentum-dependence of light quark distributions in the proton sea. The calculations will also provide predictions for experiments planned at Fermilab and JPARC. The second topic is the fundamental question of how spin and strangeness are related in the production of strange particles. We will consider reactions in which a hyperon and its antiparticle (e.g. Lambda and anti-Lambda) are created by the annihilation of an antiproton and a proton. Our calculations will focus on recent spin transfer measurements at CERN, which disagree with all theoretical predictions. We will also calculate cross sections and spin observables for the experiments planned by the PANDA collaboration at GSI/FAIR, which will extend the CERN measurements to higher energies. This work will be carried out with undergraduate research assistants from Seattle University, which has a diverse student population and a high percentage of women physics majors. The student research experience will be complementary to coursework, and provide an integration of classroom learning and the excitement of contemporary research. Students will receive training in research methods and scientific communication. They will work in teams, mentor younger students and present their work in papers, posters and talks at meetings of professional societies. They will also share their work with the local campus community in seminars and events sponsored by Seattle University student research organizations.

该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。在这个项目中，我们研究了理论核物理中与强子(例如质子、中子及其反粒子)的结构和它们的相互作用有关的两个主题。第一个主题是一个基本问题，即强子的性质(例如动量和自旋)如何在其组成部分：夸克、反夸克和胶子之间分配。本文将使用两个理论框架。在第一种情况下，强子涨落为介子-重子对，强子的部分子分布由涨落中介子和重子的部分子分布决定。第二种是用统计模型计算强子的部分子分布。这项研究将解决最近的实验对理论提出的突出挑战之一，即质子海中轻夸克分布的动量依赖性。这些计算还将为费米实验室和JPARC计划的实验提供预测。第二个主题是一个基本问题，即在奇异粒子的产生中，自旋和奇异性是如何联系在一起的。我们将考虑超子和它的反粒子(例如，兰姆达和反兰姆达)通过一个反质子和一个质子的湮灭而产生的反应。我们的计算将集中在欧洲核子研究中心最近的自旋转移测量上，这与所有的理论预测不一致。我们还将为GSI/FIRE的熊猫合作计划的实验计算截面和自旋可观测值，这将把CERN的测量扩展到更高的能量。这项工作将与西雅图大学的本科生研究助理一起进行，西雅图大学的学生群体多样化，物理专业的女性比例很高。学生的研究体验将与课程工作相辅相成，并提供课堂学习和当代研究兴奋的综合。学生将接受研究方法和科学交流方面的培训。他们将以小组形式工作，指导年轻的学生，并以论文、海报和在专业协会会议上的演讲形式展示他们的工作。他们还将在西雅图大学学生研究组织赞助的研讨会和活动中与当地校园社区分享他们的工作。