Search for the Production of Four Top Quarks at CMS

该学生将在CMS中寻找四个顶夸克的产生。在标准模型中，这个过程的横截面大约是一个飞谷仓。由于磁盘上有超过100/fb的LHC Run 2数据（其中一半尚未被分析），CMS现在应该对这个非常罕见的过程敏感。在Run 3（2021）的第一年预计会有类似数量的数据，这有效地保证了在该学生期间发现标准模型过程。相反，如果标准模型预测被排除在外，这将是一个明显的标志，表明物理学超出了标准模型。该学生将与欧洲和其他地方的CMS合作者合作，分析2018年和2021年的数据。他们将执行模拟和数据驱动技术来评估背景和优化选择，并开发和改进深度机器学习技术来增强信号的重要性。他们将在内部会议和会议上展示他们的研究结果，并在撰写一篇或多篇发表研究结果的论文中发挥主导作用。他们还将花一小部分时间为CMS合作执行操作和其他任务，包括轮班和跟踪器模拟工作。

The student will search for the production of four top quarks at CMS. In the standard model, this process has a cross section of approximately one femtobarn. With over 100/fb of LHC Run 2 data on disk (half of which has not yet been analysed), CMS should now be sensitive to this very rare process. A similar amount of data is expected in the first year of Run 3 (2021) which effectively guarantees a discovery of the standard model process during the time period of this studentship. If, in contrast, the standard model prediction is excluded, it would be a clear sign physics beyond the standard model.The student will work with CMS collaborators, in Europe and elsewhere, to analyse the 2018 and 2021 data. They will perform simulations and data-driven techniques to evaluate the backgrounds and optimise the selection, and develop and improve deep machine learning techniques to enhance the signal significance. They will present their results at internal meetings and conferences, and play a leading role in writing one or more papers publishing the results.They will also spend a fraction of their time performing operational and other tasks for the CMS collaboration, including taking shifts and working on tracker simulations.