通过高动量转移16O和12C的(p,d)反应寻找原子核中的张量力

项目名称： 通过高动量转移16O和12C的(p,d)反应寻找原子核中的张量力

项目编号： No.11305007

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 王涛峰

作者单位： 北京航空航天大学

项目金额： 30万元

中文摘要： 张量力在介子的交换作用中发挥了重要作用，在核力中提供了重要的吸引作用。其重要性已经在对氘核及α粒子结合能的解释中得到了验证。在这些核中D波的混合是张量力存在的重要证据。但是张量力在涉及重核的模型中都没有被明确地考虑到。然而，最近的实验表明张量力在丰中子核的幻数和单粒子轨道排序变化中可能发挥着重要的作用。在理论方面，最近对轻核进行的ab-initio计算亦显示出张量力在形成质量数至12的核的过程中发挥着不可取代的作用。遗憾的是，实验方面仅有氘核和α粒子中存在张量力的证据，因此，通过实验寻找重核中张量力存在的直接证据是非常有必要的。本项目旨在通过探测2 fm-1处的核子动量分布来研究12C 和 16O中张量力效应。在RIBLL2上测量能量为400-1600MeV的12O(p,d)11C和16O(p,d)15O反应在零度的截面，根据不同末态下截面的能量依赖性来研究高动量成分张量力效应。

中文关键词： 张量力；动量转移；中子捕获截面；自发裂变；

英文摘要： The tensor forces play an important role in the pion exchange interactions that provide the most important attraction in nuclear forces. The importance of the tensor forces has been demonstrated to reproduce the properties of nuclear matter as well as to explain the binding energy of deuteron and alpha particles. In contrast, this interaction has not been included explicitly in nuclear models such as mean field models of heavier nuclei. However, recent experiments have revealed a possible important role of the tensor forces in the changes of magic numbers and the orders of single-particle orbitals in neutron-rich nuclei. In theory, recent ab-initio type calculations of light nuclei also show essential importance of the tensor forces for binding nuclei up to mass number 12. Unfortunately, experimental evidences other than deuteron and alpha are indirect and thus we need more direct evidence in heavier nuclei. Present project aims to look for effects of tensor force in 12C and 16O nuclei by deducing the internal momentum distribution at around 2 fm-1 where the effect of the tensor interactions appears as an enhancement of probability. The 2 fm-1 is 400 MeV/c momentum transfer which corresponds to 800 MeV proton beam. By measuring the differential cross sections of (p, d) reaction on 12C and 16O targets at 0 d

英文关键词： Tensor Force；Momentum Transfer；Neutron Capture Cross Sections；Spontaneous Fission；