CAREER: Uncertainty Estimates in Low-Energy Nuclear Physics

核物理中的许多重要反应不能用目前可用的实验技术来测量。例如，在太阳中，两个质子聚变到一个质子(一个中子和一个质子的束束态)的过程的反应概率是一个重要的过程。然而，它不能通过实验测量，只有理论计算才能提供这个速率。在缺乏实验指导的情况下，量化理论上的不确定性变得很重要。为了解决这些问题，该项目将使用分析和数值方法来计算与天体物理相关的反应速率和新的核间相互作用参数，这将对更大的核物理界有用。具体地说，PI和他的学生将使用使用有效场论构建的核相互作用。在这种理论方法中，可以对核相互作用模型进行系统的改进，以提高计算的精度。这种方法的固有误差将使用数值技术来确定。这个项目不仅将使我们能够更好地了解宇宙中发生的重要的核过程，而且该项目还将为学生和博士后研究员提供一个激动人心的培训场所，并开展外展社区活动。该项目旨在利用有效场论提高我们对电弱过程的理解。在无指数有效场论的统一框架下，计算了少核子系统中的一些弱过程。具体地说，将从理论上研究测量良好的氚衰变半衰期，以获得对质子-质子聚变和弱质子在氦-3上俘获的高精度描述。此外，PI和他的学生将研究哈密顿量的内在误差以及在“完全”有效场论中产生的相关电弱电流。PI将使用新的技术来分析通过手征电势和相关的电弱电流计算的矩阵元素中的不确定性，以便正确地解释逐阶哈密顿的固有误差。然后，PI将与他的合作者一起使用这些结果来计算可观测到的数据，例如半衰期或总衰减率，这些数据目前已被测量到新的精度和正确的误差估计。由此产生的相互作用和电流将提供给核理论界。

Many important reactions in nuclear physics cannot be measured with currently available experimental techniques. For example, the reaction probability of the process in which two protons fuse to a Deuteron (a bound state of a neutron and a proton) is an important process in the sun. However, it cannot be measured experimentally and only theoretical calculations can provide this rate. In the absence of guidance from experiment, it becomes important to quantify theoretical uncertainties. To address these issues, this project will use analytical and numerical methods to calculate reaction rates for astrophysically relevant reaction rates and new parametrizations of the internuclear interaction that will be useful to the larger nuclear physics community. Specifically, the PI and his students will use nuclear interactions constructed using effective field theory. In this theoretical approach, the nuclear interaction model can be systematically improved to improve the accuracy of the calculation. Intrinsic error of this approach will be determined using numerical techniques. This project will allow not only for a better understanding of important nuclear processes occurring in the universe, but also the project will provide a stimulating training ground for students and postdoctoral fellows and outreach community activities.This project aims at improving our understanding of electroweak processes using effective field theory. A number of weak processes in few-nucleon systems will be calculated within the unified framework of 'pionless' effective field theory. Specifically, the well-measured decay half-life time of tritium will be studied theoretically in order to obtain a highly accurate description for proton-proton fusion and weak proton capture on Helium-3. Furthermore, the PI and his student will study the intrinsic error of Hamiltonians and associated electroweak currents generated in 'pionfull' effective field theory. The PI will use novel techniques to analyze uncertainties in matrix elements calculated with the chiral potential and the associated electroweak currents in order to account correctly for the intrinsic error of the Hamiltonian order-by-order. With his collaborators, the PI will then use these results to calculate observables such as half-life times or total decay rates that are currently measured to new accuracy and with correct error estimates. The resulting interactions and currents will be made available to the nuclear theory community.