Hyperon Physics at BESIII

The BESIII detector on the BEPCII collider collected the world’s largest dataset at the peaks of $$J/\psi$$ , $$\psi(3686)$$ and $$\psi(3770)$$ . The use of polarization and entanglement states in multidimensional angular distribution analysis can provide new probe to the production and decay characteristics of hyperon anti hyperon pairs. In a recent series of studies, significant transverse polarization in hyperon decay has been observed in $$J/\psi$$ , $$\psi(3686)$$ decaying into the $$\Lambda\bar{\Lambda}$$ , $$\Sigma^{+}\bar{\Sigma}^{-}$$ , $$\Xi^{0}\bar{\Xi}^{0}$$ , and $$\Xi^{-}\bar{\Xi}^{+}$$ final states. The weak decay parameters of hyperons and antihyperons are also independently determined for the first time. The most accurate testing for direct $$CP$$ violation has been achieved.