基于协变张量方法的ψ衰变到γB(B|ˉ)的分波分析

Covariant Tensor Formalism for Partial Wave Analyses of ψ Decays into γBB

最近BESⅡ合作组在pp-不变质量谱阈值附近观测到一个增强．利用协变张量方法,给出了ψ辐射衰变道ψ→γpp-,γΛΛ-,γΞΞ-分波分析的理论公式．通过蒙特卡罗模拟,还给出了J／ψ→γPP-中光子和质子的角分布,它们可以作为将来对这些道分波分析的有用参考．

Recently BESⅡ collaboration observed an enhancement near the p-↑p invariant mass spectrum.Using the covariant tensor formalism, here we provide theoretical formulae for the partial wave analysis （PWA） of the ψ radiative decay channels ψ → γp-↑p, γ∧-↑∧, γ∑-↑∑, γΞ-↑Ξ. By performing the Monte Carlo simulation, we give the angular distributions for the photon and proton in the process of J/ψ →γp-↑p, which may serve as a useful reference for the future PWA on these channels.