超对称对Higgs粒子衰变的贡献

A Scalar particle with mass about 125 GeV was discovered by the ATLAS and CMS Collaborations in 2012. Its production and decay channels were measured. It is well believed that this new-discovered scalar particle is Higgs boson. Motivated by these recent experimental results, this project aims to study the contribution of different type of supesymmetric models to Higgs boson decays, especially to photon pair, tau lepton pair and lepton-flavour-changing final states. The radiative correction of supersymmetry particles to Higgs boson decays is calculated by using automatic-calculating packages: FeynArts, FormCalc and LoopTools. Considering the latest constraints on the parameters of different supersymmetric models from the experiment, the recent experimental results about Higgs boson are explained. This will give new constraints on supersymmetric models. We also investigated lepton-flavour-changing decays of Higgs boson contributed by R-parity violated supersymmetric models. The possibility of discovery the signal of these decays at the planning international linear collider and Higgs factory is discussed. This project will help experimentalists to measure the couplings of Higgs boson to the Standard Model particles precisely, to find supersymmetry, and to test the conservation of the R-parity in the future high-energy experiments.

本项目研究不同超对称模型对Higgs粒子某些衰变道（实验结果与标准模型预言不一致的衰变道和R-宇称破坏的最小超对称模型预言的轻子味改变衰变道）的贡献。通过精确计算不同超对称模型对这些衰变过程的辐射修正，解释最新的与Higgs粒子相关的实验结果，研究这些实验结果对超对称模型参数的限制。并研究在将来的国际正负电子对撞机ILC，Higgs工厂上探测到Higgs粒子的轻子味改变衰变过程的可能性和可行性。本项目的研究不仅有助于精确测量Higgs粒子与标准模型粒子之间的耦合，而且可以为将来的高能物理实验发现SUSY、检验R-宇称是否守恒提供理论依据。

质量为126GeV，在标准模型中起着关键作用的Higgs标量粒子的发现标志着标准模型的巨大成功。精确测量Higgs粒子的性质是当前高能物理界最前沿最紧迫的研究课题，也是正在筹建中的对撞机的主要物理目标。本项目主要研究超对称模型对Higgs粒子与τ轻子对的耦合和Higgs粒子的电荷宇称（CP）性质，超对称模型以及其它新物理模型对Higgs粒子与τμ轻子数改变的耦合，以及带电Higgs粒子在超对称模型中的物理迹象。研究发现了一系列可以放大τ轻子相关CP破坏效应的实验可观测量，以及强烈依赖于Higgs粒子CP混合角的实验可观测量。Higgs粒子轻子数破坏过程的相关研究表明该过程可以给新物理模型很强的限制。该项目的研究可以为在未来对撞机上精确测量轻子数破坏过程，精确研究Higgs粒子的CP性质，以及寻找超出标准模型的新物理提供理论依据和方法指导。