ATLAS Beyond the Standard Model Searches in Multileptonic Final State

该项目与大型强子对撞机Run-3的启动很好地同步，Run-3将收集前所未有的质子-质子碰撞，并达到对撞机所能达到的最高能量。该项目是苏塞克斯大学领先的数据密集型项目的一部分，该项目利用实验收集的Run-2和Run-3数据样本，在ATLAS上搜索多轻子最终态中超越标准模型（BSM）的新物理现象。多轻子“特征”是一系列令人兴奋的BSM场景的特征，其目的是阐明基础物理学中一些最紧迫的问题——比如我们宇宙中暗物质的起源，或者中微子质量的基本性质。有待探索的模型包括产生弱相互作用的超对称粒子，即带电子和中性微子，或者产生在中微子质量跷跷板模型中遇到的外来重中性轻子。苏塞克斯参与ATLAS的主要技术是通过实验的触发系统，包括ATLAS探测器的未来升级。与他们的角色相称，并与他们的其他研究和培训活动协同，学生将为苏塞克斯大学对ATLAS实验的技术承诺做出贡献。近年来，苏塞克斯学生在触发器相关活动中做出了重大贡献的例子包括ATLAS内部探测器系统的软件开发，或电子触发器关键特性的表征。

The project is well synchronised with the start of the LHC Run-3, which will lead to the collection of unprecedented amounts of proton-proton collisions at the highest energies ever reached at a collider. The project is part of Sussex's leading programme of data-intensive searches for new physics phenomena Beyond the Standard Model (BSM) in multileptonic final states at ATLAS, using Run-2 and Run-3 data samples collected by the experiment. Multileptonic "signatures" are characteristic of a wide range of exciting BSM scenarios, which aim to shed light on some of the most pressing questions in fundamental physics - such as the origin of dark matter in our universe, or the fundamental nature of neutrino masses. Models to be explored include the production of weakly interacting supersymmetric particles known as charginos and neutralinos, or the production of exotic heavy neutral leptons as encountered in seesaw models of neutrino masses.Sussex's principal technical involvement in ATLAS is through the experiment's trigger system, including focus on future upgrades of the ATLAS detector. Commensurately with their role, and in synergy with their other research and training activities, the student will contribute to Sussex's technical commitments to the ATLAS experiment. Example of trigger-related activities that Sussex students have significantly contributed to in recent years include software developments for the ATLAS Inner Detector system, or the characterisation of key properties of electron-based triggers.