Polarization study of P-wave charmonium radiative decay into a light vector meson at e^(+)e^(-) collider experiment  

作　　者：Yong-Qing Chen Peng-Cheng Hong Zhuo Chen Wei Shan Wei-Min Song 陈永清;洪鹏程;陈琢;单葳;宋维民(School of Physics and Electronics,Hunan Normal University,Changsha 410081,China;College of Physics,Jilin University,Changchun 130012,China)

机构地区：[1]School of Physics and Electronics,Hunan Normal University,Changsha 410081,China [2]College of Physics,Jilin University,Changchun 130012,China

出　　处：《Chinese Physics C》2025年第1期19-34,共16页中国物理C(英文版)

基　　金：Supported by the National Natural Science Foundation of China(11805064,11975118);State Key Laboratory of Nuclear Physics and Technology,Peking university(NPT2025KFY03)。

摘　　要：In this paper,a formalism is presented for the helicity amplitude analysis of the decays Ψ(2S)→γ_(1)χ_(c)J,χ_(c)J→γ_(2)V(V=p^(0),φ,ω)(subscripts 1 and 2 are used to distinguish the two radiative photons),and the polarization expressions of the P-wave charmonia χ_(c)J and the vector mesons p^(0),φ,ω for experimental measurements at an electron-positron collider.In addition,we derive formulae for the angular distributions of χ_(c1,2)→γV to extract the degree of transverse polarization P_(T) of e^(+)e^(-)pairs with symmetric beam energy as well as the ratios of two helicity amplitudes x(in χ_(c1) decays)and x,y(in χ_(c2) decays),which represent the relative magnitudes of transverse to longitudinal polarization amplitude.The results are validated by Monte Carlo simulation.Finally,the statistical sensitivity of P_(T),x,and y are estimated based on the large Ψ(2S)data samples collected at current and proposed future e^(+)e^(-)colliderexperiments.

关 键 词：P-wave charmonia POLARIZATION vector meson angular distribution spin density matrix 

分 类 号：O57[理学—粒子物理与原子核物理]