US-Tunisia Cooperative Research: Medium Modifications of the N-N Interaction Studied in Large-Basis Shell-Model Calculations

0096785巴雷特描述：该奖项是为了支持一个联合研究项目的博士布鲁斯R。巴雷特，教授，物理系，亚利桑那大学，图森，亚利桑那州和博士穆罕默德斯利姆Fayache，助理教授，物理系，突尼斯大学，突尼斯，突尼斯。 这项研究解决了核结构物理学中一个长期存在的问题，即两个核子（质子和/或中子）之间的自由空间相互作用如何在原子核内改变（即，核物质）。 这两位科学家中的一位先前进行了计算，以研究这些介质修改对核子-核子相互作用的张量和自旋轨道分量的影响，但仅在相互作用核子的相当有限的模型空间中。 新的理论技术的形式大的基础，无核心壳模型的方法，现在允许这样的计算在显着更大的模型空间。 两位研究人员将研究介质修改对核子-核子相互作用的影响如何通过将计算扩展到2 hw激发之外的模型空间来改变。 其他核结构问题也将使用大基，无核壳模型方法进行研究，如远离稳定谷的核的性质。范围：该奖项将允许一名美国科学家与一名突尼斯科学家在一个领域合作，每个人都有解决某些理论物理问题的不同和独特的方法的知识。 要解决的问题，核结构的微观计算，是PI和其他美国科学家全力参与的问题。 该提案符合INT的目标，即支持美国与外国在互利领域的科学合作。 该项目的资金由国际方案司和物理司提供。

0096785BarrettDescription: This award is for support of a joint research project by Dr. Bruce R. Barrett, Professor, Department of Physics, University of Arizona, Tucson, Arizona and Dr. Mohamed Slim Fayache, Assistant Professor, Physics Department, University of Tunis, Tunis, Tunisia. The research addresses one of the long-standing problems in nuclear-structure physics, that of how the free-space interaction between two nucleons (protons and /or neutrons) is modified inside a nucleus (i.e., inside nuclear matter). One of these two scientists has previously performed calculations to study these medium-modification effects on the tensor and spin-orbit components of the nucleon-nucleon interaction, but only in a fairly limited model space for the interacting nucleons. New theoretical techniques in the form of the large-basis, no-core shell-model approach now permit such calculations in significantly larger model spaces. The two investigators will study how the medium-modification effects on the nucleon-nucleon interaction are changed by extending the calculations to model spaces beyond excitations of 2hw. Other nuclear-structure problems will also be investigated using the large-basis, no-core shell-model method, such as the properties of nuclei far from the valley of stability.Scope: This award will allow a US scientist to collaborate with a Tunisian scientist in an area where each has knowledge of different and unique methods for solving certain theoretical physics problems. The problem to be addressed, the microscopic calculations of nuclear structures, is one in which the PI and other US scientists are fully engaged. This proposal meets the INT objective of supporting US-foreign scientific collaboration in areas of mutual benefit. Funding for this project is provided by the Division of International Programs and the Division of Physics.