纯中性事例事例顶点z向坐标的最小二乘拟合(英文)

A Kinematic Fit Method for All-Photon Events

对于相互作用顶点z坐标未知的纯中性事例,发展了一种运动学拟合的方法．经蒙特卡罗样本检验,拟合所用的程序是合理可靠的．把该方法用于ψ′→γπ0→γγγ蒙特卡罗样本,得到了更高的选择效率．该方法可普遍应用于正负电子对撞实验中纯中性事例的分析．

An improved kinematic fit method is developed for analyzing all-photon events, where the interaction point is unknown. The fitting algorithm is checked with Monte Carlo samples to ensure that the fitting program works properly. This is applied to the Monte Carlo simulated ψ（2S） decays. A higher efficiency is achieved. This method can be generally applied to analyzing all-photon events at electron-positron collider.