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

Abstract

Based on $1.89\times 10^8$ $J/\psi \to \Lambda \bar{\Lambda }$ 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 $J/\psi \to \Lambda \bar{\Lambda }$ 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 $J/\psi \to \Lambda \bar{\Lambda }$ process is expected to reach $\mathcal{O}$~$(10^{-5})$ when the electron beam polarization is 80\%.