Precision tests of EWK sector and direct searches for new physics with di-boson production

EWK 部门的精确测试和通过双玻色子生产直接搜索新物理

• 批准号: 1669021
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1669021
• 关键词: Precision; tests; EWK; sector; direct

The initial focus of this project is to search for new physics resonances in the electroweak (EWK) sector using data collected fromATLAS at the LHC. The searches are looking for particles such as the Randell-Sundrum Graviton, G, and the heavy vector boson W0.The decay channels investigated in this project are ZZ or WZ llqq, where W and Z are the charged and neutral vector bosons l is a leptonand q is a quark. The lepton is either an electron or a muon and the quarks form jets which can be resolved as either two jets or one largejet depending on the momentum of the quarks. An important part of these searches are the modeling of the background events and any sys-tematics associated with the analysis. If no new physics is found then limits will be placed on the production rate for hypothetical signals.The project will also set limits on the anomalous Triple Gauge Boson Couplings (aTGC), e.g. WW Z, and anomalous Quartic Gauge Bo-son couplings (aQGC), e.g. WZ X WZ. This is done using the effective Lagrangian approach which investigates the contributions ofloop and off-shell processes to lower energy levels which are achievable at the LHC. The investigations into this look at the kinematic distri-butions of the WW or WZ to see if there are any signicant changes due these processes.The authorship task for ATLAS associated with this project is the investigation into the observed innefficiency of the muon trigger full scanchains in the case of close by muons. The full scan procedure is an event filter process which searches the whole detector without usingany information from the other levels of the trigger. The observed innefficiency is 10% per muon when muons are close each other atdR < 0:3. The aim of the task is to investigate the problem, its causes and to find a solution to increase the innefficiency.

该项目的最初重点是利用在LHC上从ATLAS收集的数据在电弱（EWK）扇区中寻找新的物理共振。该项目研究的衰变通道是ZZ或WZ llqq，其中W和Z是带电和中性矢量玻色子，l是轻子，q是夸克。轻子可以是电子也可以是μ子，夸克形成喷流，根据夸克的动量，喷流可以分解为两个喷流或一个大喷流。这些搜索的一个重要部分是背景事件和与分析相关的任何系统的建模。如果没有发现新的物理现象，那么将对假设信号的产生率进行限制。该项目还将对反常的三重规范玻色子耦合（aTGC）（例如WW Z）和反常的四重规范玻色子耦合（aQGC）（例如WZ X WZ）进行限制。这是使用有效的拉格朗日方法完成的，该方法研究了循环和离壳过程对大型强子对撞机可实现的较低能级的贡献。对这一问题的研究着眼于WW或WZ的运动学分布，以了解这些过程是否引起任何显著的变化。与该项目相关的ATLAS的作者任务是研究在μ子接近的情况下观察到的μ子触发全扫描的无效性。全扫描过程是一个事件过滤过程，它在不使用触发器其他层次信息的情况下搜索整个检测器。当μ子在dR < 0：3时相互靠近时，观察到的效率为10%/μ子.该任务的目的是调查问题及其原因，并找到解决方案，以提高效率。