电磁Dalitz衰变K^(*)(892)→Kl^(+)l^(-)的研究  

Electromagnetic Dalitz Decays K^(*)(892)→Kl^(+)l^(-)

作　　者：谭英华 王文欢[1] 张振宇[1] 周详[1] TAN Yinghua;WANG Wenhuan;ZHANG Zhenyu;ZHOU Xiang(School of Physics and Technology,Wuhan University,Wuhan 430072,Hubei,China)

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072

出　　处：《武汉大学学报（理学版）》2022年第3期221-226,共6页Journal of Wuhan University:Natural Science Edition

基　　金：国家自然科学基金(U2032114)。

摘　　要：研究了电磁Dalitz衰变K^(*)(892)→Kl^(+)l^(-)(l=e,μ),通过矢量介子主导(vector meson dominance,VMD)模型的跃迁形状因子(transition form factor,TFF)计算了K^(*)(892)→Kl^(+)l^(-)对K^(*)(892)→Kγ的相对衰变分支比,给出了双轻子不变质量谱和轻子极角角分布。K^(*)(892)→Ke^(+)e^(-)和K^(*)(892)→Kμ^(+)μ^(-)对K^(*)(892)→Kγ的相对衰变分支比分别为(0.818±0.004)%和(0.027±0.001)%。本文的研究结果为在北京谱仪Ⅲ(Beijing spectrometerⅢ,BESⅢ)实验和未来的超级陶粲装置(Super Tau-Charm Facility,STCF)实验上研究奇异粲介子K^(*)(892)的辐射衰变及电磁Dalitz衰变过程提供了必要的理论支持。The electromagnetic(EM)Dalitz decays K^(*)(892)→Kl^(+)l^(-)(l=e,μ)are studied.The relative branching fractions of K^(*)(892)→Kl^(+)l^(-)to K^(*)(892)→Kγare calculated by transition form factors(TFFs)of vector meson dominance(VMD)model,and the dileptonic invariant mass spectra and the leptonic polar angular distributions are given.The relative branching fractions of K^(*)(892)→Ke^(+)e^(-)and K^(*)(892)→Kμ^(+)μ^(-)to K^(*)(892)→Kγare(0.818±0.004)%and(0.027±0.001)%,respectively.The research results in this paper provide necessary theoretical supports for the study of radiative decays and EM Dalitz decays of strange charmed mesons K^(*)(892)in Beijing SpectrometerⅢ(BESⅢ)experiment and future Super Tau-Charm Facility(STCF)experiment.

关 键 词：奇异矢量粒子 矢量介子主导模型 跃迁形状因子 衰变分支比 

分 类 号：O572.33[理学—粒子物理与原子核物理]