Top-Higgs sector and simplified models

希格斯粒子的发现提出了一些基本的理论问题。在运行1之后，我们没有实验迹象表明观察到的窄希格斯共振不是基本粒子。然而，对标准模型紫外线结构的研究表明，对于这样一个基本态，我们可以从LHC希格斯数据中提取关于高能标度下标量势的相关信息，例如希格斯势的稳定性，所谓的平凡性约束，以及紫外线下标量粒子质量的一般行为。另一方面，在QCD和许多其他物理领域，对称性破缺是通过强相互作用和相关物理自由度的变化发生的。在这种情况下，低能可重整化的希格斯-拉格朗日量必须用更高维的算符来扩展，这些算符来自于能量不超过弱标度太多的新的强相互作用。此外，顶夸克仍然是标准模型中第二个神秘的粒子，它以其巨大的质量区别于其他费米子。如果假设基本粒子的味结构，特别是汤川耦合的模式，在高尺度下有一个共同的起源，那么大的顶夸克质量可能表明，顶汤川耦合经历了比其他费米子更强的重整化群演化。这是一个强有力的迹象，表明可能存在超越标准模型的新粒子，使顶夸克成为新物理搜索的主要目标。最重要的是，大的顶-希格斯耦合表明，我们也许应该把希格斯玻色子和顶夸克看作一个强耦合的物理部门，无论标准模型之外的基础物理是什么。在这个项目中，我们提出了一个全面的研究顶-希格斯部门作为一个工具，寻找超越标准模型的物理。这包括测量的希格斯属性，新的LHC签名和超越标准模型，subjet方法作为一种新的分析方法，并调查顶部希格斯部门演变到高能量尺度。

The discovery of a Higgs particle raises fundamental theoretical questions. After Run 1we have no experimental indication that the observed narrow Higgs resonance is not anelementary particle. However, studies of the ultraviolet structure of the Standard Modelsuggest that for such an elementary state we can extract relevant information from the LHC Higgs data about the scalar potential at high energy scales, such as the stability of the Higgs potential, the so-called triviality bound, and the general behavior of scalar particle masses in the ultraviolet. On the other hand, in QCD and in many other areas of physics, symmetry breaking occurs through strong interactions and a shift in the relevant physical degrees of freedom. In that case the low-energy renormalizable Higgs Lagrangian would have to be extended by higher-dimensional operators, originating from new strong interactions at energies not too far above the weak scale.Furthermore, the top quark remains the second mysterious particle in the Standard Model, distinguished from the other fermions by its large mass. If one assumes the flavor structure of elementary particles, in particular the pattern of Yukawa couplings, has a common origin at a high scale, the large top quark mass could indicate that the top Yukawa coupling experiences stronger renormalization group evolution than the other fermions. This is a strong indication of possible new particles beyond the Standard Model, making the top quark a prime target for new physics searches. Most importantly, the large top-Higgs coupling suggests that we should maybe look at the Higgs boson and the top quark as one strongly coupled physics sector, no matter what the underlying physics beyond the Standard Model might be.In this project we propose a comprehensive study of the top-Higgs sector as a tool to look for physics beyond the Standard Model. This includes the measured Higgs properties, new LHC signatures in and beyond the Standard Model, subjet methods as a new analysis approach, and an investigation of the top-Higgs sector evolved to high energy scales.