RUI: Studies of Heavy Quarkonium Spectroscopy with Belle and Belle II

20世纪最重要的智力成就之一是粒子物理学标准模型（SM）的发展。这个模型成功地将当时已知的所有基本粒子划分为具有相似量子特性的等级。到目前为止，这个模型的有效性已经被位于瑞士日内瓦附近的欧洲核子研究中心（CERN）的大型强子对撞机（LHC）发现的希格斯玻色子所证实。然而，目前存在的标准模型留下了许多关于宇宙的问题，包括为什么希格斯玻色子的质量具有它所具有的价值这样的基本问题。为了回答这些问题，有必要超越标准模型所描述的宇宙的现状，进入下一个发展阶段，即超越标准模型（BSM）。BSM物理学研究的问题包括：为什么物质在宇宙中支配着反物质；物质的基本成分、夸克和轻子的质量值；夸克和轻子之间混合的大小；以及暗物质的性质。这个项目的重点是研究特殊类型的粒子介子的性质，介子的性质可以揭示超出标准模型的基本物理信息。该奖项的工作将使用日本高能加速器研究组织（KEK）实验室的Belle和Belle- ii实验收集的数据。新的Belle-II是围绕一个不对称电子-正电子对撞机的相互作用区域建造的。贝尔项目的主要目标是探测由夸克-反夸克对组成的粒子，即介子。特别是那些由粲夸克（粲夸克）和底夸克（底夸克）组成的介子。这些介子是用量子色动力学（QCD）理论在SM中描述的。通过研究这些介子，人们可以探索BSM的基本物理过程，如电荷宇称（CP）破坏、罕见介子衰变和可能表明暗物质存在的外来粒子。日本KEK的Belle实验拥有世界上最大的数据样本，记录了质量范围为10 GeV的底部共振，即所谓的Upsilon共振。在这些共振能量下，电子-正电子束粒子产生B介子的概率要高得多，这使得实验人员能够获得大量的统计数据并观察到罕见的现象。路德学院研究小组的这个RUI项目的中心目标是研究底铵和相关状态的光谱，重点是共振状态，探索我们对量子色动力学（QCD）的理解的局限性，并提高对晶格QCD（用于对QCD计算进行计算机预测的技术）的理论理解。路德学院的项目为本科生提供了一个不同寻常的机会，让他们有意义地参与到世界领先的实验中，参与Belle数据分析的各个方面，并为升级后的实验Belle II开发软件工具。该项目的广泛影响具有示范性，通过为高中生开设大师班，为爱荷华州东北部农村地区的学生和教师提供更多的科学研究机会，并通过地区女孩编程组织为年轻女性提供计算机会。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

One of the major intellectual achievements of the 20th century was the development of the Standard Model (SM) of particle physics. This model succeeded in classifying all of the elementary particles known at the time into a hierarchy of groups having similar quantum properties. The validity of this model to date was confirmed by the discovery of the Higgs boson at the Large Hadron Collider (LHC) at the CERN laboratory near Geneva Switzerland. However, the Standard Model as it currently exists leaves open many questions about the universe, including such fundamental questions as to why the mass of the Higgs boson has the value it has. To answer these questions, it is necessary to go beyond the present picture of the Universe described by the Standard Model to the next phase of development, Beyond the Standard Model (BSM). Investigations in BSM physics probe such questions as why matter dominates over anti-matter in the Universe, the values of the masses of the fundamental constituents of matter, the quarks and the leptons, the size of the mixings among the quarks, and separately among the leptons, and the properties of dark matter. This project focuses on the study of the properties of special types of particles, mesons, whose nature can reveal information about fundamental physics beyond the Standard Model. The work in this award will use data collected at the Belle and Belle-II experiments at the High Energy Accelerator Research Organization (KEK) laboratory in Japan. The new Belle-II is built around the interaction region of an asymmetric electron-positron collider. The main goal of the Belle program is to detect particles made of a quark-anti-quark pair, so called mesons. In particular those mesons made of charm quarks (charmonium) and bottom quarks (bottomonium). These mesons are described in the SM by the theory of Quantum Chromodynamics (QCD). By studying these mesons, one can probe for BSM fundamental physics processes such as Charge Parity (CP) violation, rare meson decays and possible exotic particles which could indicate the presence of Dark Matter. The Belle Experiment at KEK in Japan has the world's largest data samples recorded at the bottomonium resonances in the mass range of 10 GeV, the so-called Upsilon resonances. At these resonant energies the electron positron beam particles have a much higher probability of producing B mesons, allowing experimenters to acquire large statistics and observe rare phenomena. The central aim of this RUI program of research by the Luther College group is to study the spectroscopy of bottomonium and related states, with a focus on resonant states that probe the limits of our understanding of Quantum Chromodynamics (QCD) and improving the theoretical understanding in lattice QCD (the techniques used to make computer predictions of QCD calculations). The Luther College program provides an unusual opportunity for undergraduate students to become meaningfully involved in a world-leading experiment, taking part in every aspect of Belle data analysis, and in the development of software tools for the upgraded experiment, Belle II.The broader impacts of the program are exemplary, fostering greater exposure to scientific research among students and teachers in rural Northeast Iowa, through masterclasses for High School students and providing computational opportunities for young women through the regional Girls Who Code Organization.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.