权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Getting a flavour for New Physics with precision measurements of tree-level beauty decays

通过精确测量树级美丽衰减来体验新物理学

基本信息

批准号：
ST/R004536/1
负责人：
Matthew Kenzie
金额：
$ 59.3万
依托单位：
University of Cambridge
依托单位国家：
英国
项目类别：
Fellowship
财政年份：
2019
资助国家：
英国
起止时间：
2019 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FR004536%2F1
关键词：
Getting flavour New Physics precision

项目摘要

Elementary particle physics has an incredibly successful underlying theoretical framework known as the Standard Model which has produced a succession of successful predictions and subsequent discoveries in recent decades. This culminated in the discovery of the Higgs Boson in 2012, which was the last missing piece of the Standard Model. However, there are still a multitude of observed phenomena which the Standard Model cannot explain and the focus of this research is understanding the matter-antimatter asymmetry of the universe. In the hot early universe matter and antimatter should have been created in equal amounts; this is the simple conversion of energy into matter via Einstein's famous equation, E=mc^2. Once the universe cooled the matter and antimatter would have "annihlated" to leave behind an abundance of electromagnetic radiation. This electromagnetic radiation we see today as the cosmic microwave background, the static seen on an untuned televsion. However, there is clearly an imbalance as we also see large amounts of matter, which make up the stars, galaxies and ourselves whilst no antimatter is left at all. We can understand some part of this as being due to charge-parity symmetry (that which relates matter to antimatter) being broken. In the intial stages of matter-antimatter creation charge-parity violation results in a small excess of matter, which goes on to make up the observable universe of today, after the majority annihilates with the antimatter to leave behind the electromagnetic radiation still echoing around the universe. The problem is that the amount of charge-parity violation predicted by the theoretical framework underlying our understanding of elementary particle physics is nowhere near enough (a factor several billion off) to account for the observed matter to electromagnetic radiation ratio of the universe. This project uses data from the Large Hadron Collider to look for new fundamental physics particles which can help to explain the matter-antimatter discrepancy. By analysing millions of matter and antimatter decays produced at the LHCb experiment we can observe the subtle differences between them. The parameters we determine in this project are of particular interest because they can be measured completely independently of any input from the theoretical framework, i.e. independently of any prior knowledge. We can then use these parameters to prove the existence, and predict the behaviour, of new fundamental physics particles which explain why we live in a matter dominated universe and hence why we have atoms, molecules and life itself.

基本粒子物理学有一个非常成功的基本理论框架，被称为标准模型，在最近几十年里产生了一系列成功的预测和随后的发现。2012年，希格斯玻色子的发现达到了顶峰，这是标准模型中最后一块缺失的部分。然而，仍然有许多观察到的现象是标准模型无法解释的，本研究的重点是了解宇宙的物质-反物质不对称。在炎热的早期宇宙中，物质和反物质应该是等量产生的；这是通过爱因斯坦著名的方程E=mc^2将能量转化为物质的简单过程。一旦宇宙冷却，物质和反物质就会“湮灭”，留下丰富的电磁辐射。我们今天看到的这种电磁辐射就是宇宙微波背景，也就是在调谐不到的电视上看到的静电。然而，这显然是不平衡的，因为我们也看到了大量的物质，这些物质组成了恒星、星系和我们自己，而根本没有留下任何反物质。我们可以理解这部分是由于电荷-宇称对称性(与物质有关的反物质)被打破。在物质-反物质产生的初始阶段，电荷-宇称破坏导致了少量过剩的物质，在大部分物质湮灭后，留下了仍然在宇宙中回声的电磁辐射，这些物质继续构成了今天的可见宇宙。问题是，支撑我们理解基本粒子物理学的理论框架预测的电荷宇称破坏的量远远不足以解释观测到的物质与宇宙电磁辐射的比率(一个数十亿倍)。该项目使用大型强子对撞机的数据来寻找新的基本物理粒子，这些粒子可以帮助解释物质-反物质的差异。通过分析LHCb实验产生的数百万种物质和反物质衰变，我们可以观察到它们之间的细微差别。我们在这个项目中确定的参数特别令人感兴趣，因为它们可以完全独立于理论框架的任何输入进行测量，即独立于任何先验知识。然后，我们可以使用这些参数来证明新的基本物理粒子的存在，并预测其行为，这些粒子解释了为什么我们生活在一个由物质主导的宇宙中，从而解释了为什么我们有原子、分子和生命本身。