Ab initio theory of light and medium mass nuclei

原子核是由质子和中子与源自量子色动学基本理论的力相互作用而形成的量子多体系统。从核子组成和核子间相互作用出发，对原子核进行精确的处理一直是核物理学的一个长期目标。** 该项目的目标是发展轻和中等质量核的核结构和核反应的预测性从头算理论。这样的理论是需要了解稀有的同位素设施，如ISAC在TRIUMF研究的外来核，为了解重要的天体物理学的核反应，为了解重要的未来能源的产生，以及为核过程中的基本对称性的测试融合反应。与此同时，它提供了一个反馈的质量核子间的迭代作为输入这些计算，并最终有助于提高我们的知识的核子核子相互作用，特别是仍然没有完全理解的三核子相互作用。** 在这个建议中，我们结合了联合收割机的从头计算方法能够描述轻核的束缚态与微观集团方法发展来描述核集团的反应。由此产生的方法提供了一个统一的描述从质子和中子之间的核子间相互作用的束缚和非束缚的核状态。 我们将应用这种方法来提高我们对奇异核的理解，如9He，11N或17C，描述晕核，如11Be或11Li。使用最先进的核力，包括三核子相互作用，我们将计算对天体物理学重要的核反应速率，包括7Be（p，γ）8B，3He（4He，γ）7Be，2H（α，γ）6Li和4He（nn，γ）6He，这些反应在宇宙环境中发生的低能量下难以或不可能测量。我们还将研究聚变反应，如3H（d，n）4He和非中子11B（p，alpha）8Be相关的未来能源生产。我们将研究6He的β衰变，这是对标准模型之外的物理学的一个重要测试。我们也将致力于中等质量核的从头计算，其中一个主要目标是改进无中微子双β衰变矩阵元的计算。最后，该项目的长期目标是计算对恒星合成12C和16O重要的反应。预计这些反应的理论理解的复杂性需要exa规模的计算。

Atomic nuclei are quantum many-body systems made by protons and neutrons interacting with forces that originate from the fundamental theory of Quantum Chromo-Dynamics. The exact treatment of nuclei starting from the constituent nucleons and the inter-nucleon interactions among them has been a long-standing goal in nuclear physics. ******The goal of this project is to develop a predictive ab initio theory of nuclear structure and nuclear reactions for light and medium mass nuclei. Such a theory is needed for understanding of exotic nuclei investigated at rare isotope facilities like ISAC at TRIUMF, for understanding of nuclear reactions important for astrophysics, for understanding of fusion reactions important for the future energy generation as well as for the testing of fundamental symmetries in nuclear processes. At the same time, it provides a feedback on the quality of inter-nucleon iteractions used as input to these calculations and ultimately helps to improve our knowledge of the nucleon-nucleon interaction, and in particular of the still-not-completely-understood three-nucleon interaction. ******In this proposal, we combine an ab initio nuclear structure approach capable to describe bound states of light nuclei with a microscopic cluster method developed to describe reactions of nuclear clusters. The resulting method provides a unified description of both bound and unbound nuclear states starting from inter-nucleon interactions among protons and neutrons. We will apply this method to improve our understanding of exotic nuclei such as 9He, 11N, or 17C, to describe halo nuclei like 11Be or 11Li. Using state-of-the-art nuclear forces including the three-nucleon interaction, we will calculate rates of nuclear reactions important for astrophysics including 7Be(p,gamma)8B, 3He(4He,gamma)7Be, 2H(alpha,gamma)6Li and 4He(nn,gamma)6He that are difficult or impossible to measure at low energies at which these reactions occur in cosmic environments. We will also investigate fusion reactions such as 3H(d,n)4He and the aneutronic 11B(p,alpha)8Be relevant for future energy generation. We will study beta decay of 6He that is being measured as an important test of physics beyond the Standard Model. We will also contribute to ab initio investigatinos of medium mass nuclei with one of the major goals to improve calculations of the neutrinoless double-beta decay matrix elements. Finally, a long-term goal of this project is the calculation of reactions important for stellar synthesis of 12C and 16O. It is anticipated that the complexity of theoretical understanding of these reactions equires exa-scale computing.**