Searching for New Physics with the CMS experiment at the LHC

欧洲核子研究中心（CERN）的大型强子对撞机（LHC）将升级为高亮度强子对撞机（High Luminosity LHC HL LHC），大幅提高质子质子对撞率。CMS实验将同时升级，以确保我们在高强度的强子对撞机环境中获得更精确的物理测量和对新物理的更高灵敏度。CMS 1级触发系统在实验的数据获取链中起着至关重要的作用：在几微秒内，它就能决定哪些碰撞足够有趣，可以存储起来供以后分析。作为HLL HC升级的一部分，1级触发系统将使用尖端技术取代。它将由数百个基于fpga的定制电路板组成，由数千条光链路连接，总带宽约为20万千兆比特。CMS 1级触发系统将首次能够访问来自跟踪器的信息，从而实现可在1级触发中运行的粒子重建和识别算法类型的范式转换。作为CMS合作的一部分，该学生将在HL-LHC触发系统的算法开发中发挥关键作用，参与算法过程概念设计的所有阶段，在模拟p-p碰撞中测量其性能，在固件中实现这些算法，并在电子板上测试这些算法。该学生还将参与在CERN建立测试系统，并与连接组件进行集成测试。学生将获得计算机编程和FPGA固件开发的技能。除了学习用于固件开发的经典硬件描述语言外，学生还将使用现代工具，如Vivado HLS，以更高层次的抽象来表达算法的关键组件。大型强子对撞机刚刚开始第三次运行，CMS实验将收集有史以来最大的数据集。除了HL-LHC一级触发研究外，该学生还将在扩展希格斯扇区模型或暗扇区模型的背景下寻找BSM物理的证据。最终将被利用的状态将包括轻希格斯玻色子或半可见喷流，它们将使用广泛使用神经网络（如Graph NNs和自动编码器）的技术进行重建。在开发新的搜索和解释结果时，我们与NExT研究所的理论家密切合作。

The Large Hadron Collider LHC at CERN will be upgraded to become the High Luminosity LHC HL LHC icantly increasing the rate of proton proton collisions. The CMS experiment will be upgraded at the same time in order to ensure that we will get more precise physics measurements and greater sensitivity to new physics in the intense HL LHC environment. The CMS level 1 trigger system plays a critical role in the experiment's data aquisition chain: Within a few microseconds it decides which collisions are sufficiently interesting to store for later analysis. As part of the HLL HC upgrades the level 1 trigger system will be replaced using cutting edge technologies. It will consist of hundreds of FPGA-based custom electronics boards, connected by several thousand optical links with a total bandwidth of roughly 200 000 Gbits. For the first time the CMS level1 trigger system will have access to information from the tracker, enabling a paradigm shift in the types of particle reconstruction and identification algorithms that can be run in the level1 trigger. As part of the CMS collaboration, the student will play a key role in developing algorithms for the HL-LHC trigger system, working on all stages of the process conceptual design of the algorithms, measuring their performance in simulated p-p collisions implementing these algorithms in firmware and testing these algorithms on the electronics boards. The student will also be involved in setting up test systems at CERN, and performing integration tests with connected components. The student will gain skills in computer programming and FPGA firmware development. In addition to learning classic hardware description languages for firmware development, the student will also use modern tools like Vivado HLS for expressing key components of algorithms in higher-level abstractions. The LHC has just started Run 3 and the CMS experiment will be collecting its largest ever dataset. In addition to the HL-LHC level-1 trigger studies, the student will also work on searches for evidence of BSM physics in the context of extended Higgs sector models or dark sector models. The final states that will be exploited will include light higgs bosons or semi-visible jets, which will be reconstructed using techniques that make extensive use of neural nets such as Graph NNs and autoencoders. We work closely with theorists within the NExT Institute when developing new searches and interpreting results.