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arXiv · 2306.15602

Prospects of $CP$ violation in $\Lambda$ decay with polarized electron beam at STCF

Sheng Zeng·Yue Xu·Xiao Rong Zhou·Jia Jia Qin·Bo Zheng
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Abstract

Based on $1.89 \times 10^8$ $J/\psi \rightarrow \Lambda \bar{\Lambda}$ Monte Carlo (MC) events produced from a longitudinally-polarized electron beam, the sensitivity of $CP$ violation of $\Lambda$ decay is studied with fast simulation software. In addition, the $J/\psi \rightarrow \Lambda \bar{\Lambda}$ decay can also be used as a process to optimize the detector response using the interface provided by the fast simulation software. In the future, STCF is expected to obtain 3.4 trillion $J/\psi$ events, and the statistical sensitivity of $CP$ violation of $\Lambda$ decay via $J/\psi \rightarrow \Lambda \bar{\Lambda}$ process is expected to reach $\mathcal O$~$(10^{-5})$ when the electron beam polarization is 80\%.

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Sheng Zeng, Yue Xu, Xiao Rong Zhou, Jia Jia Qin, Bo Zheng. 2023-06-27. Prospects of $CP$ violation in $\Lambda$ decay with polarized electron beam at STCF. https://doi.org/10.1088/1674-1137%2Face9c5

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