Strong interaction effects in exclusive B decays

独家 B 衰变中的强相互作用效应

• 批准号: SAPGP-2014-00002
• 负责人: Ahmady, Mohammad
• 金额: $ 1.82万
• 依托单位: Mount Allison University
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Group
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=612382
• 关键词: Strong; interaction; effects; exclusive; decays

With the Large Hadron Collider (LHC) first run successfully completed in 2013 and a wealth of data being continuously analysed and published, the physics of the B mesons, i.e. mesons containing a b quark, has entered a new exciting era. One of the four main experiments at the LHC, namely the LHCb experiment, is dedicated to the study of the B mesons. Their numerous decay channels offer the opportunity to make precision tests of the Standard Model (SM) and perhaps more interestingly, to discover new physics beyond the SM. Data taking will resume in 2015 at peak energy and higher luminosity. In the next 5 years, various observables will be measured with increasing precision by the LHCb collaboration and theory input will clearly be required to interpret the data as well as to guide future experiments in this field. In this research, we focus on rare exclusive B decays to light mesons, i.e. B decays to specific final products. Such decays are especially appealing because they are relatively easy to access experimentally especially in an environment like the LHC. On the other hand, the theory of such decays is challenging because they involve strong interactions effects which are not computable using perturbation theory in Quantum Chromodynamics (QCD), the fundamental modern theory of strong interactions. In our research, we model these effects by using a relatively new technique which involves exploiting a correspondence between QCD in physical spacetime and a string theory in a higher dimensional curved space called anti de Sitter (AdS) space. This correspondence is called AdS/QCD. At the same time, we will investigate signals of new physics in those rare B decays. These rare decays are sometimes quite susceptible to the interference from much heavier particles that may be out there but have not been discovered yet. Our proposed investigation is to have a better understanding of these interferences which can then be compared with the experimental data from the LHC. This comparison will hopefully give us some clues on how the SM can be extended towards a more complete theory. With our research, we hope to contribute to the efforts of the particle physics community to discover new physics at the LHC. At the same time, we are testing AdS/QCD which offers insights into the unsolved problem of confinement of quarks in hadrons.

随着大型强子对撞机（LHC）在2013年成功完成，并且不断分析和发布大量数据，B Mesons的物理学，即包含B Quark的Mesons的物理学，已经进入了一个新的令人兴奋的时代。 LHC的四个主要实验之一，即LHCB实验，是针对B膜的研究。他们的众多衰减频道为对标准模型（SM）进行精确测试提供了机会，也许更有趣的是，发现SM之外的新物理学。数据获取将在2015年以峰值能量和更高的发光度恢复。在接下来的5年中，通过LHCB协作和理论输入的精确度升高，将显然需要衡量各种可观察到的物品，以解释数据以及指导该领域的未来实验。 在这项研究中，我们专注于罕见的独家B衰变对介体，即B衰减特定的最终产品。这样的衰减特别有吸引力，因为它们相对容易实验访问，尤其是在LHC等环境中。另一方面，这种衰减的理论具有挑战性，因为它们涉及强烈的相互作用效应，这些效应是使用量子铬动力学（QCD）（QCD）的强大相互作用的效果，这是强烈的互动的基本现代理论。在我们的研究中，我们通过使用一种相对较新的技术来对这些效果进行建模 在更高维度的弯曲空间中，称为抗De Sitter（ADS）空间。此通信称为AD/QCD。同时，我们将研究在罕见的B衰变中新物理学的信号。这些罕见的衰变有时很容易受到可能存在但尚未发现的较重颗粒的干扰。我们提出的研究是对这些干扰有更好的了解，然后将这些干扰与LHC的实验数据进行比较。这种比较将有望为我们提供一些线索，了解如何将SM扩展到更完整的理论。通过我们的研究，我们希望为粒子物理界在LHC发现新物理学的努力做出贡献。同时，我们正在测试ADS/QCD，该广告/QCD可以洞悉未解决的夸克（Hadron）中未解决的问题。