次最小超对称模型中的Higgs物理

Although the Standard Model (SM) of particle physics has testified to be successful in describing the electroweak interactions, the problems of electroweak symmetry breaking and the origin of the mass have been unsolved. One of the important task of the running Large Hadron Collider (LHC) is hunting for the Higgs boson, which provides the mass to the elementary particle in the SM. Recently, both the ATLAS and CMS collaborations at LHC have announced the discovery of a new boson around 125 GeV with the properties similar to the Higgs boson predicted by the SM, and the excess of the Higgs di-photon signal can be interpreted reasonably in the supersymmetric models. Therefore, the phenomenlogy study of Higgs boson in supersymmetric models is a very popular program.. Focusing on the popular issue on looking for the Higgs bosons, and following closely the updating experimental data at the LHC, we carry out the program by investigating the properties of the Higgs bosons and the sparticles in the next-to-minimal supersymmetric model (NMSSM). The research will serve as a guide for the experimenters to hunt for the Higgs bosons and testify the right theory.

虽然粒子物理标准模型在解释电弱物理方面取得了巨大的成功，但是电弱对称性破缺以及与其相关的质量起源问题仍未解决，而目前正在运行的大型强子对撞机LHC的主要任务之一就是寻找引起质量起源的Higgs粒子。LHC最新实验结果表明在125GeV附近存在一个与标准模型性质相似的玻色子，其双光子信号的超出在超对称模型中可以得到合理解释。因此在超对称模型中对Higgs性质研究是当前非常热门的课题之一。. 本项目正是围绕目前寻找Higgs粒子这一热点问题展开，紧密跟踪LHC不断更新和丰富的实验数据，在次最小超对称模型NMSSM中研究Higgs粒子性质以及LHC探测超对称粒子的能力，从而为实验寻找Higgs粒子以及检验超对称理论提供理论指导。

结合LHC公布的Higgs实验数据，我们在最小超对称标准模型（MSSM）和次最小超对称标准模型（NMSSM）中分别对比研究了LHC和光子-光子对撞机上类标准模型双Higgs的产生。研究成果主要包括：（1）在MSSM和NMSSM中，LHC上双Higgs产生主要是来自胶子-胶子凝聚过程。相比标准模型(SM)预言，产生截面最大可以抬高10倍。（2）在光子-光子对撞机上，MSSM中双Higgs产生截面的抬高主要来自stau圈图的贡献，产生截面最大可以抬高18倍；而在NMSSM中主要来自标量top夸克圈图贡献。