在ATLAS实验上测量矢量玻色子散射过程以及对相关新物理的寻找

The precise measurements of Standard Model rare processes: the vector boson scattering processes, will help to greatly improve the understanding of the Higgs mechanism, and its unitarization effect in electroweak interactions and the electroweak symmetry breaking. Currently, many Standard Model Vector Boson Scattering processes haven't been measured yet at sufficiently high statistical significances at the LHC. This project proposes to use the proton-proton collision data at the center-of-mass energy of 13TeV collected by the ATLAS detector during Run-II with an integrated luminosity at around 120/fb, so that the vector boson scattering signatures can be expected to be measured at the significance of 3 to 5 sigma or more in many new scattering processes such as WZ, ZZ, Z+gamma in association with two jets. Besides, the measurements will also be used to perform the search for new physics through anomalous gauge couplings, parameterized with Effective Field Theory. Finally, by means of the statistical combination of different vector boson scattering channels, the sensitivities towards the searches for new physics can be further improved. This project is also a natural extension and expansion of the topic of Z+photon diboson scattering measurement that the applicant has led and finished in ATLAS Run-I.

精确地测量与分析标准模型所预言的矢量玻色子散射等稀有过程，对于全面而深入理解希格斯机制、电弱相互作用中的幺正性，以及对称性自发破缺性质具有十分重要的意义。目前，LHC大型强子对撞机实验尚未以足够高的统计显著度观测到很多标准模型矢量玻色子散射过程。本项目拟采用ATLAS探测器Run-II实验阶段在13TeV质心能量下即将收集的约120/fb的质子-质子对撞数据，通过测量WZ, ZZ, Z+光子等双玻色子伴随双强子喷注的矢量玻色子散射过程，预期在这些末态中首次实现3倍到5倍标准偏差以上统计显著度的测量。这些物理过程的测量也将被用来研究规范玻色子反常耦合效应，同时通过有效场理论来参数化反常耦合系数，探寻新物理，并最终可通过不同衰变道的联合统计分析，进一步提高新物理寻找的灵敏度。本项目也是申请人在ATLAS的Run-I实验阶段，所负责并完成的Z+光子双玻色子散射研究项目的自然延伸与扩充。

精确地测量与分析标准模型所预言的矢量玻色子散射（VBS）等稀有过程，对于全面而深入理解希格斯机制、电弱相互作用中的幺正性，以及对称性自发破缺性质具有十分重要的意义。目前，LHC大型强子对撞机实验尚未以足够高的统计显著度观测到很多标准模型矢量玻色子散射过程。本项目采用了ATLAS探测器Run-II实验阶段在13TeV质心能量下即将收集的约140/fb的质子-质子对撞数据，通过测量WZ, ZZ, Z+光子等双玻色子伴随双强子喷注的矢量玻色子散射过程，在这些末态中首次实现5倍标准偏差以上统计显著度的测量(Observation)。本项目也是申请人在ATLAS的Run-I实验阶段，所负责并完成的Z+光子双玻色子散射研究项目的自然延伸与扩充，完成VBS过程超过5倍标准偏差的高统计显著度测量对未来开展基于VBS的规范反常耦合与其他新物理寻找奠定了扎实的基础。