Abstract

In this paper, we present a feasibility study of the first measurement of the longitudinal polarization of a muon from the \(\tau\)-lepton decay to extract the Michel parameter \(\xi^{\prime}\) at the future Super Charm-Tau Factory (SCTF). The expected number of \(\mu^{-}\to e^{-}\nu_{\mu}\bar{\nu}_{e}\) events on the full SCTF data was estimated, possible background processes were studied, and methods of their suppression were suggested. Statistical accuracy was estimated to be \(\sigma_{\xi^{\prime}}\approx 0.02\), which enables a new verification of the Standard Model at high precision level.

中文翻译：

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Super Charm-T​​au工厂的Tau-Lepton衰减中的Michel参数$$ {\ xi ^ {\ prime}} $$的测量

摘要

在本文中，我们提出了从\（\ tau \）-轻子衰变中首次测量μ子的纵向极化以在未来提取米歇尔参数\（\ xi ^ {\ prime} \）的可行性研究。超级魅力头工厂（SCTF）。估计了完整SCTF数据上预期的\（\ mu ^ {-} \ to e ^ {-} \ nu _ {\ mu} \ bar {\ nu} _ {e} \）事件的数量，可能的后台进程是进行了研究，并提出了抑制它们的方法。统计准确性估计为\（\ sigma _ {\ xi ^ {\ prime}} \大约0.02 \），这使得可以在高精度级别上对标准模型进行新的验证。