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

0096785barrett描述：该奖项是为了支持由亚利桑那州图森市亚利桑那大学物理系教授Bruce R. Barrett博士和突尼斯突尼斯市突尼斯大学物理系助理教授Mohamed Slim Fayache博士共同开展的一项研究项目。该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（即核物质内部）被修改。这两位科学家中的一位先前已经进行了计算，以研究这些介质修正对核子-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进行了计算。以大基、无核壳模型方法为形式的新理论技术现在允许在更大的模型空间中进行这样的计算。两位研究者将通过将计算扩展到超过2hw激励的模型空间来研究介质修饰对核子-核子相互作用的影响是如何改变的。其他核结构问题也将使用大基、无核壳模型方法进行研究，例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各自拥有解决某些理论物理问题的不同和独特方法的领域进行合作。要解决的问题是核结构的微观计算，这是PI和其他美国科学家全力参与的问题。该提案符合INT在互利领域支持美国与外国科学合作的目标。该项目的资金由国际项目部和物理部提供。

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.