摘要
电磁达利兹衰变过程对介子结构非常敏感,可以提供了解介子结构的丰富信息,在约束(g-2)μ的不确定度方面也发挥着重要作用.近期,北京谱仪Ⅲ研究和发表了对几个重要达利兹衰变的测量结果,包η'→γe^+e^-,J/ψ→Pe^+e^-(P=η',η/π0),η'→ωe^+e^-等.对这些过程的研究都是世界上的首次发现和测量,深化了我们对于介子结构和介子相互作用的理解.更多的相关工作仍在进行之中,预期它们将会进一步促进测量和理论的比较,也会对超出标准模型的新物理有一定的敏感度.
EM Dalitz decays could be sensitive and provide very rich information about meson structures,and they play an important role in constraining the uncertainties to( g- 2)μ. BEPCⅢ has performed and published several Dalitz decays,including η’ →γe^+e^-,J /ψ→Pe^+~e-( P = η’,η and π0),η’→ωe^+e^- etc. These processes are all observed and measured for the first time,furthering our knowledge about meson structures and meson interactions. Many more related work is ongoing and there will be more results to come,which will further test the theory against the measurements and could be sensitvie to the new physics beyond the standard model.
基金
Supported by National Natural Science Foundation of China(U1232105)
Ministry of Science and Technology(2015CB856700)