Searching for Physics Beyond the Standard Model

寻找标准模型之外的物理学

• 批准号: 170141-2013
• 负责人: London, David
• 金额: $ 4.15万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569547
• 关键词: Searching; Physics; Beyond; Standard; Model

The ultimate goal of particle physics is to find the theory that unifies all the forces and particles in Nature. A first step has been taken with the unification of the electromagnetic and weak forces into a single "electroweak" force. The Standard Model (SM) of particle physics, which includes the electroweak and the strong forces, successfully explains essentially all known experimental data. Nevertheless, it is clearly not the final theory -- only two of the four forces are unified, and the SM leaves many questions unanswered. Thus, there must be "physics beyond the SM," that is, phenomena that cannot be explained by the SM alone. The search for this "new physics" (NP) is the most important problem facing particle physicists today. There were a number of hints of NP over the past 4-5 years, particularly in b -> s transitions. These were first seen at the "B-factories" BaBar and Belle in various B-meson decays. The hadronic experiments CDF and DØ supported this trend, finding disagreements with the SM predictions in several other B decay modes. Putting all the results together, it appeared that b -> s NP might well be present. Unfortunately, this has not been supported by the LHC: LHCb has remeasured a number of the above quantities, and finds results in agreement with the SM. The bottom line is that there are now fewer hints of NP than there were before. Even so, there are still potential signals of NP in several different areas. There are hints of NP in certain B and D decays, in t-tbar production at hadron colliders, and even in the decay of the Higgs. Furthermore, NP models generally predict the existence of new, exotic particles, which might be produced at the LHC. My research projects touch many of these areas. They all have one common goal: to participate in the search for new physics.

粒子物理学的最终目标是找到统一自然界中所有力和粒子的理论。第一步是将电磁力和弱力统一为一个单一的“电弱”力。粒子物理学的标准模型（SM），包括电弱力和强作用力，成功地解释了基本上所有已知的实验数据。然而，它显然不是最终的理论--四种力中只有两种是统一的，SM留下了许多问题没有答案。因此，一定存在着“超越SM的物理学”，也就是说，存在着不能仅用SM来解释的现象。寻找这种“新物理学”（NP）是当今粒子物理学家面临的最重要的问题。 在过去的4-5年里，有许多NP的暗示，特别是在B -> s转换中。这些最早是在“B工厂”BaBar和贝儿的各种B介子衰变中发现的。强子实验CDF和DALF支持了这一趋势，发现在其他几种B衰变模式中与SM预测不一致。把所有的结果放在一起，似乎B -> s NP很可能存在。不幸的是，这并没有得到LHC的支持：LHCb重新测量了上述的一些量，并发现结果与SM一致。底线是，现在NP的提示比以前少了。 即便如此，在几个不同的领域仍然存在NP的潜在信号。在某些B和D衰变中，在强子对撞机产生的t-tbar中，甚至在希格斯粒子的衰变中，都有NP的迹象。此外，NP模型通常预测新的、奇异的粒子的存在，这些粒子可能在LHC中产生。我的研究项目涉及其中许多领域。他们都有一个共同的目标：参与寻找新的物理学。