主讲人：郭奉坤，中科院理论物理研究所研究员
时 间：2025年7月3日14:30
地 点：物电学院A栋316
联系人：姚德良 戴凌云
讲座摘要：The X(3872) has been discovered for more than 20 years, and debates on its internal structure are still ongoing. One obstacle in settling the issue is that its pole position (that is, its mass and width) has not been precisely determined. Furthermore, it was believed that there were no isospin-1 partners of the X(3872). In this talk, I will show that from the X(3872) properties, isopin-1 charmonium-like states with J^PC=1^++ quantum numbers must exist as virtual states, and thus as threshold cusps. I will explain why the signals have been elusive so far and in which reactions signals are expected. I will also show that a combined analysis of the BESIII and LHCb data using chiral effective field theory with three-body effects leads to the so-far most precise determination of the X(3872) pole position. The X(3872) is found to be a quasi-bound state below the \bar D^0 D^{*0} threshold with a significance of 2.8\sigma. By evaluating the compositeness with range corrections, the X(3872) is found to be a consistent with a hadronic molecule. Predictions and suggestions for further measurements will be discussed.
主讲人简介：郭奉坤，中国科学院理论物理研究所研究员。2002 年于山东大学物理学院获得理学学士学位，2007年于中国科学院高能物理研究所获理学博士学位，随后在德国于利希研究中心以及波恩大学从事博士后研究工作并担任课题负责人，2015 年加入理论物理研究所。长期从事强子谱、有效场论等方面的研究工作。近年来代表工作包括：发现重强子谱中近阈结构与 S 波吸引相关的规律；提出利用三角奇点精确测量近阈粒子束缚能的方法，与传统方法相比可大幅提高测量精度；对正宇称粲介子的数个疑难同时给出自然的解释等。2021 年获得国家杰出青年科学基金资助。PANDA 实验理论顾问组成员，HADRON, Chiral Dynamics, Erice 核物理讲习班等国际会议的国际顾问委员会成员。在 RMP, PRL 等期刊发表论文 180 余篇，总引用 1 万余次。
