在中国北京正负电子对撞机二期运行的北京谱仪III（BESIII）实验团队宣布发现了一种全新的亚原子粒子——“胶球”（glueball），实现了该粒子从理论预测到实验观测的突破。2026年8月5日，南京大学的金山教授在国际高能物理大会（ICHEP）上代表团队宣布了这一成果。胶球是一种完全由强相互作用的媒介粒子“胶子”自相互作用结合而成的全新复合粒子，打破了传统强子必须包含夸克的固有认知。
在微观物理中，强核力负责将原子核束缚在一起，并由无静止质量的胶子负责传递。胶子不仅能够与夸克相互作用，将夸克束缚成对或三夸克组合形成质子和中子，胶子之间还可以彼此结合聚集成胶球。然而，在粒子对撞产生的大量常规夸克态背景中甄别胶球极其困难，导致全球物理学界在过去近半个世纪的搜寻中始终未能获得确凿证据。
早在2011年，BESIII探测器便首次捕捉到了名为X(2370)的候选新粒子信号。在随后的十余年间，科研团队系统分析了超过100亿个可能涉及X(2370)的碰撞衰变事例，排除了所有其他夸克态假设，并于7月在线发表了该粒子的完整物性图谱。胶球的实验证实为检验强相互作用理论提供了关键基准，尤其是为揭示无质量的胶子如何通过强相互作用动力学机制生成宏观质量提供了至关重要的实验证据。
Physicists operating the Beijing Spectrometer III (BESIII) experiment at the Beijing Electron-Positron Collider II have announced the discovery of a "glueball"—a novel subatomic particle composed purely of force-carrying gluons. Presenting at the International Conference on High Energy Physics (ICHEP) on August 5th, Jin Shan of Nanjing University revealed that comprehensive data analyses confirm the particle's existence, ending nearly five decades of unfulfilled experimental searches for these hypothetical pure-force bound states.
In fundamental physics, the strong nuclear force binds atomic nuclei through massless gauge bosons known as gluons. While gluons typically interact with quarks to form conventional composite particles like protons and neutrons, theoretical models dictate that gluons can also bind directly with one another to produce glueballs. However, isolating glueball signatures from the dense background of conventional quark-based particles produced during high-energy collisions has historically presented immense experimental hurdles.
The BESIII collaboration first detected the candidate resonance, designated X(2370), in 2011. Over subsequent years, researchers analyzed more than 10bn collision events involving X(2370) to methodically rule out competing standard quark explanations, publishing the particle's complete physical properties online in July. The experimental confirmation of the glueball provides critical benchmarks for quantum chromodynamics, offering crucial insights into how the strong interaction generates physical mass from underlying massless force carriers.
Source: Physicists nab the elusive glueball
Subtitle: Make it stick
Dateline: 8月 20, 2026 03:29 上午