Search for H->cc in the VH production mode and flavour-taggin development

Vid Homsak将利用位于瑞士日内瓦的大型强子对撞机（LHC）的ATLAS探测器收集的数据，对希格斯玻色子进行深入探索。虽然希格斯玻色子是在2012年发现的，但我们的知识仅限于它与W和Z玻色子以及第三代夸克和带电轻子的相互作用。研究希格斯玻色子与第二代夸克（如粲夸克）的相互作用，对于证实希格斯机制在解释三代物质粒子中的有效性至关重要，这三代物质粒子的质量从最轻的（第一代）到最重的（第三代）不等。希格斯衰变为粲夸克（H->cc）的探测是一个重大的挑战，因为它的分支分数只有3%，而在LHC中产生的粲夸克主要被背景过程所掩盖。这项工作不仅将推进我们对希格斯->cc耦合的理解，而且还可能揭示标准模型之外的新物理。除了希格斯玻色子的工作之外，Vid还将为增强重味喷注标记做出重大贡献。他将积极参与由ATLAS Common Physics小组领导的合作努力，旨在改进这一关键工具的性能。Vid的参与扩展到在第24版中推导GN 2的光射流比例因子，这将涉及应用创新方法来补充现有的“翻转”标记器。这种方法包括在外推框架中实施一种新的方法，用于精确估计不确定性，特别是在源自长寿命粒子、转换和强子相互作用的B-/c标记错误建模的背景下。Vid将负责采用自下而上的方法生成数据集，利用它们从数据中提取系统变化，并且随后将这些变化传播到风味标记校准数据接口。

Vid Homsak will utilize the data collected by the ATLAS detector at the Large Hadron Collider (LHC) in Geneva, Switzerland, for in-depth exploration of the Higgs Boson. Although the Higgs Boson was discovered in 2012, our knowledge is limited to its interactions with the W and Z bosons, as well as quarks and charged leptons of the third generation. The study of the Higgs boson's interaction with a second-generation quark, such as the charm quark, is crucial for substantiating the validity of the Higgs mechanism in explaining the three generations of matter particles, which differ in mass from the lightest (first generation) to the heaviest (third generation). The detection of Higgs decay into charm quarks (H->cc) presents significant challenges, as its branching fraction is merely 3%, and charm quark production at the LHC is predominantly obscured by background processes. This endeavour will not only advance our understanding of the Higgs->cc coupling but also hold the potential to unveil new physics beyond the standard model.In addition to his work on the Higgs Boson, Vid will make significant contributions to the enhancement of heavy-flavor jet tagging. He will be an active participant in the collaborative efforts led by the ATLAS Common Physics group, aimed at refining the performance of this critical tool. Vid's involvement extends to deriving light jet scale factors for GN2 in release 24, which will involve the application of an innovative approach to complement the existing "flip" tagger. This approach includes the implementation of a new method into the extrapolation framework for the precise estimation of uncertainties, particularly in the context of b-/c-tagging mismodeling originating from long-lived particles, conversions, and hadronic interactions.Vid will take on the responsibility of generating datasets with a bottom-up approach, employing them to extract systematic variations from the data, and subsequently propagating these variations to the flavor tagging Calibration Data Interface.