近日，美国布朗大学Lingfeng Li团队研究了CEPC的味物理学：总体视角。2025年9月18日出版的《中国物理C》杂志发表了这项成果。
研究组基于《环形正负电子对撞机（CEPC）技术设计报告》标定的基准亮度，系统探讨了CEPC的味物理研究前景。CEPC采用多模式运行方案以应对多样化科研任务：在Z玻色子运行模式下，通过产生4万亿个Z玻色子可实现Z玻色子耦合参数的高精度测量，而洁净的Z玻色子衰变过程产生的大量高能重味夸克与轻子，为味物理研究提供了前所未有的测量精度。研究组评估了各类物理基准测量的前景，并讨论了其对粒子物理理论及唯象模型的意义。
研究表明，凭借其突出优势与预期优异的探测器性能，CEPC在美夸克与τ轻子物理研究方面将超越或互补Belle II实验和LHCb实验，有望探测到10 TeV及以上能标的新物理现象。该潜力同样体现在探索尚未发现的稀有奇异过程、检验轻子味普适性、轻子数与重子数守恒等基本原理方面，使CEPC成为味物理研究的活跃平台。CEPC的WW阈值扫描、希格斯工厂运行模式和顶夸克对产生模式进一步强化其研究优势，特别是在测量卡比博-小林-益川矩阵元、希格斯玻色子与顶夸克的中性流味改变过程等方面。
研究组明确了实现科学目标所需的探测器性能要求与未来发展考量，并强调机器学习在创新探测器设计与先进重建算法中的关键作用。CEPC味物理研究计划不仅拓展了现有项目之外的新探索维度，更丰富了这一大科学装置的科学机遇。需要说明的是，鉴于CEPC味物理研究的丰富性，该文并非全面综述，而是通过典型案例进行深入探讨。未来仍需开展专项研究以充分发掘CEPC的味物理潜力。
附：英文原文
Title: Flavor physics at the CEPC: a general perspective
Author: Xiaocong Ai, Wolfgang Altmannshofer, Peter Athron, Xiaozhi Bai, Lorenzo Calibbi, Lu Cao, Yuzhi Che, Chunhui Chen, Ji-Yuan Chen, Long Chen, Mingshui Chen, Shanzhen Chen, Xuan Chen, Shan Cheng, Cheng-Wei Chiang, Andreas Crivellin, Hanhua Cui, Olivier Deschamps, Sébastien Descotes-Genon, Xiaokang Du, Shuangshi Fang, Yu Gao, Yuanning Gao, Li-Sheng Geng, Pablo Goldenzweig, Jiayin Gu, Feng-Kun Guo, Yuchen Guo, Zhi-Hui Guo, Tao Han, Hong-Jian He, Jibo He, Miao He, Xiaogang He, Yanping Huang, Gino Isidori, Quan Ji, Jianfeng Jiang, Xu-Hui Jiang, Jernej F. Kamenik, Tsz Hong Kwok, Gang Li, Geng Li, Haibo Li, Haitao Li, Hengne Li, Honglei Li, Liang Li, Lingfeng Li, Qiang Li, Qiang Li, Shu Li, Xiaomei Li, Xin-Qiang Li, Yiming Li, Yubo Li, Yuji Li, Zhao Li, Hao Liang, Zhijun Liang, Libo Liao, Zoltan Ligeti, Jia Liu, Jianbei Liu, Tao Liu, Yi Liu, Yong Liu, Zhen Liu, Xinchou Lou, Peng-Cheng Lu, Alberto Lusiani, Hong-Hao Ma, Kai Ma, Farvah Mahmoudi, Yajun Mao, Yaxian Mao, David Marzocca, Juan-Juan Niu, Soeren Prell, Huirong Qi, Sen Qian, Zhuoni Qian, Qin Qin, Ariel Rock, Jonathan L. Rosner, Manqi Ruan, Dingyu Shao, Chengping Shen, Xiaoyan Shen, Haoyu Shi, Liaoshan Shi, Zong-Guo Si, Cristian Sierra, Huayang Song, Shufang Su, Wei Su, Zhijia Sun, Michele Tammaro, Dayong Wang, En Wang, Fei Wang, Hengyu Wang, Jian Wang, Jianchun Wang, Kun Wang, Lian-Tao Wang, Wei Wang, Xiaolong Wang, Xiaoping Wang, Yadi Wang, Yifang Wang, Yuexin Wang, Xing-Gang Wu, Yongcheng Wu, Rui-Qing Xiao, Ke-Pan Xie, Yuehong Xie, Zijun Xu, Haijun Yang, Hongtao Yang, Lin Yang, Shuo Yang, Zhongbao Yin, Fusheng Yu, Changzheng Yuan, Xing-Bo Yuan, Xuhao Yuan, Chongxing Yue, Xi-Jie Zhan, Hong-Hao Zhang, Kaili Zhang, Liming Zhang, Xiaoming Zhang, Yang Zhang, Yanxi Zhang, Ying Zhang, Yongchao Zhang, Yu Zhang, Zhen-Hua Zhang, Zhong Zhang, Mingrui Zhao, Qiang Zhao, Xu-Chang Zheng, Yangheng Zheng, Chen Zhou, Daicui Zhou, Pengxuan Zhu, Yongfeng Zhu, Xuai Zhuang
Issue&Volume: 2025-09-18
Abstract: We discuss the landscape of flavor physics at the Circular Electron-Positron Collider (CEPC), based on the nominal luminosity outlined in its Technical Design Report. The CEPC is designed to operate in multiple modes to address a variety of tasks. At the Z pole, the expected production of 4 Tera Z bosons will provide unique and highly precise measurements of Z boson couplings, while the substantial number of boosted heavy-flavored quarks and leptons produced in clean Z decays will facilitate investigations into their flavor physics with unprecedented precision. We investigate the prospects of measuring various physics benchmarks and discuss their implications for particle theories and phenomenological models. Our studies indicate that, with its highlighted advantages and anticipated excellent detector performance, the CEPC can explore beauty and τ physics in ways that are superior to or complementary with the Belle II and Large-Hadron-Collider-beauty experiments, potentially enabling the detection of new physics at energy scales of 10 TeV and above. This potential also extends to the observation of yet-to-be-discovered rare and exotic processes, as well as testing fundamental principles such as lepton flavor universality, lepton and baryon number conservation, etc., making the CEPC a vibrant platform for flavor physics research. The WW threshold scan, Higgs-factory operation and top-pair productions of the CEPC further enhance its merits in this regard, especially for measuring the Cabibbo-Kobayashi-Maskawa matrix elements, and Flavor-Changing-Neutral-Current physics of Higgs boson and top quarks. We outline the requirements for detector performance and considerations for future development to achieve the anticipated scientific goals. The role of machine learning for innovative detector design and advanced reconstruction algorithms is also stressed. The CEPC flavor physics program not only develops new capabilities for exploring flavor physics beyond existing projects but also enriches the physics opportunities of this machine. It should be remarked that, given the richness of the CEPC flavor physics, this manuscript is not meant to be a comprehensive survey, but rather an investigation of representative cases. Uncovering the full potential of flavor physics at the CEPC will require further dedicated explorations in the future.
DOI: 10.1088/1674-1137/adf1f0
Source: http://hepnp.ihep.ac.cn/article/doi/10.1088/1674-1137/adf1f0