Ψ(2S)粒子及粲夸克偶素物理实验研究——2001年度国家自然科学奖获奖项目介绍

EXPERIMENTAL STUDIES ON PHYSICS OF THE Ψ(2S) PARTICLE AND OTHER CHARMONIUM STATES

文章介绍 2 0 0 1年度国家自然科学奖二等奖获奖成果1 ) .在北京正负电子对撞机上采集了Ψ (2S)粒子大数据样本 ,开展了粲偶素物理的广泛研究 :完成了 6个粲偶素涉及质量、宽度和衰变分支比等大批重要参数的首次测量或高精度测量 ;通过对Ψ(2S)和J Ψ强衰变性质的比较研究 ,观察到一系列反常现象 ,挑战现有理论图像 .该项研究成果对量子色动力学的检验与发展具有重要意义 ,为我国粲偶素物理实验研究的继续发展并保持先进水平奠定坚实基础 .

Using the world′s largest sample of Ψ(2S) events collected at the Beijing Electron\|Positron Collider, extensive studies on all 6 charmonium states below charm threshold have been conducted. Of more than 50 results including measurements of mass, width and branching fraction, 21 parameteers were measured for the first time, and a large part of the others were determined with the highest precision. A number of anomalies have been observed from a careful comparison of the branching fractions for various modes of exclusive hadronic decays of the J/Ψ and Ψ(2S), which pose a significant challenge to the present understanding of hadronic decays. This study is of importance to the test and development of quantum chromodynamics, and provides a solid foundation for continuing experimental studies of charmonium physics at an advanced level in China. It was awarded a 2nd Class National Science Award in 2001.