Radiative leptonic decay of heavy quarkonia  

作　　者：Junle Pei Xinchou Lou Yaquan Fang Jinfei Wu Manqi Ruan 裴俊乐;娄辛丑;方亚泉;吴金飞;阮曼奇(Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Spallation Neutron Source Science Center,Dongguan 523803,China;University of Chinese Academy of Sciences,Beijing 100049,China;University of Texas at Dallas,Richardson,TX,USA;China Center of Advanced Science and Technology,Beijing 100190,China)

机构地区：[1]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [2]Spallation Neutron Source Science Center,Dongguan 523803,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]University of Texas at Dallas,Richardson,TX,USA [5]China Center of Advanced Science and Technology,Beijing 100190,China

出　　处：《Chinese Physics C》2024年第10期114-124,共11页中国物理C（英文版）

基　　金：Supported by the National Natural Science Foundation of China(12247119,12042507)。

摘　　要：In this study,the properties of heavy quarkonia X are examined by treating them as bound states of Q and Q at the leading-order level within the non-relativistic quantum chromodynamics(NROCD)framework,where Q represents either a charm or bottom quark.The branching ratios for the radiative leptonic decays X→γl^(+)l^(-)are revisited,and the angular and energy/momentum distributions of the final state particles are analyzed in the restframe of X.Furthermore,we apply Lorentz transformations from the rest frame of X to the center-of-mass frame of l^(+)l^(-)to establish the connection between the widths Г_(x→γl^(+)l^(-))and Г_(x→l^(+)l^(-)).The comparison of the connection tothose documented in literature(divided by 2π)for various X states,such as J/Ψ,Ψ(2S),Υ(1S),and Υ(2S),shows relative differences typically around or below 10%,comparable to the next-to-leading order corrections of O(α)and 0(ν^(4)).However,we observe a significant disparity in the ratio betweenГ_(Ψ(2S)→γτ^(+)τ^(-))andГ_(Ψ(2S)→τ^(+)τ^(-)),with our prediction being four times larger than those in literature.The outcomes derived from this study have practical im.plications in describing the quantum electrodynamics radiative processes and contribute to the investigation of QCD processes associated with the decays of heavy quarkonia and searches for new physies.

关 键 词：heavy quarkonia radiative leptonic decays branching ratios 

分 类 号：O572.33[理学—粒子物理与原子核物理]