講座主題：CDF W mass anomaly from a dark sector with a Stueckelberg-Higgs portal
專家姓名：劉佐偉
工作單位：南京大學
講座時間：2022年5月20日 10:00-11:30
講座地點：騰訊會議：461-137-584
主辦單位：煙臺大學物理與電子信息學院
內容摘要：
We propose an explanation to the new W mass measurement recently reported by the CDF collaboration, which is larger than the standard model expectation by about 7 standard deviations. To alleviate the tensions that are imposed on the electroweak sector by the new W mass measurement, we carry out an analysis in the Stueckelberg extended standard model where a new neutral gauge boson appears which mixes with the two neutral gauge bosons in the electroweak sector both via the Stueckelberg mass terms and via the gauge invariant Stueckelberg-Higgs portal interaction and spoils the custodial symmetry at the tree level so that the simple relation between the W boson mass and the Z boson mass does not hold. We find that such an extension increases the W boson mass if the new gauge boson mass is larger than the Z boson mass. We further show that there exists a significant part of the parameter space in the extended model which includes the CDF mass anomaly and is consistent with the various observables at the Z pole and consistent with the ATLAS dilepton limits. The Stueckelberg Z' boson, which resolves the CDF W mass anomaly, should be searchable in future LHC experiments.
主講人介紹：
劉佐偉，南京大學物理學院教授。2003年復旦大學本科畢業；2008年美國東北大學博士畢業；2008年至2011年在美國紐約州立大學石溪分校楊振寧理論物理研究所做博士后研究；2011年至2014年在加拿大麥吉爾大學做博士后研究；2014年至2016年在清華大學任副研究員；2016年至今在南京大學任教授。長期從事高能理論研究，研究方向包括暗物質理論和唯象學研究，加速器實驗上尋找新物理的研究等。迄今發表學術論文41篇，引用2600余次，單篇最高引用328次。
