Lattice Gauge Theory at the Intensity Frontier

该奖项资助犹他大学Carleton DeTar教授的研究活动。我们目前对自然界中最基本的基本粒子和相互作用的理解被概括在所谓的“标准模型”中。不幸的是，它是不完整的。例如，它无法解释弥漫在宇宙中的暗物质。因此，物理学家几乎普遍认为，还有更多的基本粒子和相互作用有待发现。欧洲大型强子对撞机等加速器正在进行大规模的实验研究，以发现新的粒子。即使加速器的能量不足以发现它们，这些新粒子也会通过仔细的测量和基于标准模型的精确理论预测之间的差异来揭示它们的存在。只有随着实验测量精度的提高而减少预测量中的残余不确定度，这样的比较才是有效的。德塔尔教授和他的合作者正在使用最强大的计算机和代码来做出精确的预测，这些预测可以与实验测量的结果进行比较，并特别关注那些已经发现了一些诱人的差异的情况。这项工作符合国家利益，因为它加深了我们对最基本的自然规律的理解。其更广泛的影响包括培训学生和博士后研究人员编程和使用最高性能的计算机、管理大型数据集以及统计分析和提取物理上重要的信息。德塔尔教授的许多学生和博士后研究助理已经找到了在工业和学术环境中使用这些技能的工作。更严格地说，这个项目将使用晶格量子色动力学的方法来精确研究重夸克衰变的强子环境。然后，将得到的强子衰变常数和形状因子与含有这些重夸克的介子衰变的测量结果结合起来。该项目还将包括计算强相互作用对Muon反常磁矩的贡献。强子真空极化的结果值将与正在进行的高精度磁矩实验测量结果进行比较。这两个比较对标准模型的一致性和对新物理理论模型的限制提供了严格的测试。这些计算的目的是足够精确，以至于现在有必要包括虚拟光子的影响。因此，这个项目将提高我们纳入它们的能力。这个奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award funds the research activities of Professor Carleton DeTar at the University of Utah.Our current understanding of the most fundamental elementary particles and interactions in Nature is encapsulated in the so-called "Standard Model". Unfortunately, it is incomplete. For example, it can't explain the dark matter that permeates the Universe. Thus physicists almost universally believe that still more fundamental particles and interactions are yet to be discovered. A large experimental search is underway at accelerators, such as the European Large Hadron Collider, to find new particles. Even if the accelerator energy is not high enough to find them, such new particles will reveal their existence through discrepancies between careful measurements and precise theoretical predictions based on the Standard Model. Such comparisons are effective only if the residual uncertainties in the predicted quantities are reduced in tandem with improvements in the accuracy of experimental measurements. Professor DeTar and collaborators are using the most powerful computers and codes to make precise predictions that can be compared with results of experimental measurements, with particular attention to those cases where some tantalizing discrepancies have already been found. This work is in the national interest in that it furthers our understanding of the most fundamental laws of Nature. Its broader impacts include the training of students and postdoctoral research associates in programming and utilizing the highest-performance computers, in the management of large data sets, and in the statistical analysis and extraction of physically important information. Many of Professor DeTar's students and postdoctoral research associates have found jobs that utilize those skills in industrial as well as academic settings.More technically, this project will use methods of lattice quantum chromodynamics in a precision study of the hadronic environment of heavy-quark decays. The resulting hadronic decay constants and form factors are then combined with measurements of the decays of mesons containing those heavy quarks. The project will also involve the calculation of the strong-interaction contribution to the anomalous magnetic moment of the muon. The resulting value for the hadronic vacuum polarization will be compared with results of ongoing high-precision experimental measurements of the magnetic moment. Both comparisons provide stringent tests of the consistency of the Standard Model and constraints on theoretical models of new physics. These calculations are intended to be sufficiently precise that it is now necessary to include the effects of virtual photons. This project will therefore advance our ability to include them.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.