摘要：
The top quark is the heaviest particle in the Standard Model. The top-Higgs Yukawa coupling is not only the largest and important for vacuum stability, but also remarkably close to unity and expected to be modified in physics beyond the Standard Model. This talk summarizes the most accurate constraints on the top-Higgs Yukawa coupling in proton-proton collisions with the ATLAS detector, especially with the Higgs boson decaying into a pair of photons.  The four-top-quark production is a very rare top quark production process, and is sensitive to the signs of BSM physics. Compared with the measurements with Higgs boson decays, this talk highlights the first observation of four-top-quark production at LHC, where data are used to constrain the top-Higgs Yukawa coupling independently.In addition, this talk will discuss the relevant studies in the future and the upgrade of the ATLAS experiment.

报告人简介：
Dr. Shuo Han is currently a postdoctoral researcher at the Lawrence Berkeley National Laboratory (LBNL). In the past 3 years, he was leading the Higgs property measurements in the diphoton final state, as well as the searches for the Standard Model multi-top productions with the ATLAS experiment. He is also responsible for pre-production procedures of the ATLAS strip detector upgrade at the LBNL site. Shuo Han obtained his Ph.D degree from the Institute of High Energy Physics, Chinese Academy of Science (IHEP) in 2019. His PhD thesis focused on the photon identification with the ATLAS detector and the searches for Higgs production in the Z boson plus photon final state. His current interests include the precise measurements of the Standard Model and the new physics searches at the Large Hadron Collider, the novel machine learning techniques in physics analyses, and the silicon tracking detectors.