Experimental Flavor Physics

实验风味物理学

• 批准号: 1505719
• 负责人: Michael Sokoloff
• 金额: $ 60万
• 依托单位: University of Cincinnati Main Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-15 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1505719&HistoricalAwards=false
• 关键词: Experimental; Flavor; Physics

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 recently 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. These include why matter dominates over anti-matter in the Universe (CP violation), 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. Most explanations require the presence of new forces and the development of concepts that now constitute what we call physics Beyond the Standard Model (BSM). This award supports research that addresses those questions that dominate BSM physics. The research will be carried out at the LHC, which is the premier High Energy Physics particle accelerator in the world and one of the foremost facilities for answering these BSM questions.LHCb is the first experiment designed specifically to study the decays of hadrons containing b or c quarks at a hadron collider. The goal of LHCb is to identify new physics in nature by examining the properties of hadrons containing these quarks. New physics, or new forces, are manifest by particles, as yet to be discovered, which would modify decay rates and CP violating asymmetries, and thus allow new phenomena to be observed indirectly. In direct searches for new particles, the accelerator's energy must be high enough to allow the particle to be produced. In indirect searches effects of new particles can be seen even if they have a much higher mass than can be seen directly, because the effects are quantum in nature, and appear in Feynman diagrams where the particles are" virtual", so they are emitted and absorbed over short times.LHCb has operated very successfully starting in late 2010. This award will allow the study of rare decays of heavy quark systems. These decays provide a unique window into physics at an energy scale well beyond that accessible by explicit production of new particles at colliders. This is increasingly important as the limits for new physics by CMS and ATLAS increase, the only window may turn out to be in the studies of rare decays. This work will concentrate mostly on charm quark physics, the expertise of the group. These charm channels can show BSM physics in CP violation and other parity violating asymmetries. Any discovery of BSM physics would be a huge step forward in our understanding of the fundamental physics of the universe. In addition, this award will facilitate a small part of the ongoing LHCb detector upgrade that will improve the overall ability of the detector to fully exploit the LHC data.

世纪的主要学术成就之一是粒子物理学标准模型（SM）的发展。该模型成功地将当时已知的所有基本粒子分类为具有相似量子特性的组的层次结构。最近，在瑞士日内瓦附近的欧洲核子研究中心实验室的大型强子对撞机（LHC）上发现的希格斯玻色子证实了这一模型的有效性。然而，目前存在的标准模型留下了许多关于宇宙的问题。这些问题包括为什么在宇宙中物质比反物质占主导地位（CP破坏），物质的基本成分夸克和轻子的质量值，夸克之间混合的大小，以及轻子之间的混合，以及暗物质的性质。大多数解释都需要新的力的存在和概念的发展，这些概念现在构成了我们所说的超越标准模型（BSM）的物理学。 该奖项支持解决主导BSM物理学的那些问题的研究。 这项研究将在LHC上进行。LHC是世界上最先进的高能物理粒子加速器，也是回答这些BSM问题的最重要的设备之一。LHC B是第一个专门设计用于研究强子对撞机上含有B或c夸克的强子衰变的实验。LHCb的目标是通过检查包含这些夸克的强子的性质来识别自然界中的新物理。新的物理学或新的力量，是由粒子，尚未发现，这将修改衰变率和CP违反不对称性，从而允许新的现象被间接观察到。在直接寻找新粒子时，加速器的能量必须足够高，以允许粒子产生。在间接搜索中，即使新粒子的质量比直接搜索大得多，也可以看到新粒子的效应，因为这些效应本质上是量子的，并且出现在费曼图中，粒子是”虚拟的”，因此它们在短时间内被发射和吸收。LHCb从2010年底开始非常成功地运行。 该奖项将允许研究重夸克系统的罕见衰变。这些衰变为物理学提供了一个独特的窗口，其能量尺度远远超出了在对撞机上明确产生新粒子所能达到的范围。随着CMS和ATLAS对新物理学的限制越来越大，这一点越来越重要，唯一的窗口可能是研究罕见衰变。这项工作将主要集中在粲夸克物理学，该小组的专业知识。这些魅力通道可以显示CP违反和其他宇称违反不对称性的BSM物理。 BSM物理学的任何发现都将是我们理解宇宙基本物理学的一大步。此外，该奖项将促进正在进行的LHCb探测器升级的一小部分，这将提高探测器充分利用LHC数据的整体能力。