Abstract

A method is suggested that allows the first measurement of the polarization of muons from τ-lepton decays at the Super charm-tau Factory. To measure the polarization, it is proposed to use muons decayed in flight in the drift chamber of the detector, when both tracks, mother and daughter, were reconstructed by the reconstruction program. The method is based on the correlation between the muon spin and daughter electron momentum. We used a Monte Carlo simulation with the Super charm-tau Factory detector parameters to estimate the number of decayed-in-flight muons. Possible background processes were studied and methods for their suppression were proposed. The expected statistical uncertainty for muon polarization measurement is about 2%.

中文翻译：

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未来超级魅力陶工厂中轻子τ衰变的Michel参数ξ'的测量

摘要

提出了一种方法，该方法可以在超级魅力堡工厂中首次测量来自τ轻子衰变的介子极化。为了测量极化，提出了当通过重建程序重建母线和子线时，使用在检测器的漂移室内在飞行中衰减的μ子的方法。该方法基于介子自旋和子电子动量之间的相关性。我们将蒙特卡洛模拟与超级魅力头工厂检测器参数一起使用，以估计飞行中的μ子的数量。研究了可能的背景过程并提出了抑制它们的方法。μ子极化测量的预期统计不确定性约为2％。