Observation of ${\Xi }^{-}$ Hyperon Transverse Polarization in $\psi (3686)\to {\Xi }^{-}{\bar{\Xi }}^{+}$

BESIII Collaboration, M. Ablikim, M. N. Achasov +569

Using a sample of $(448.1\pm 2.9)$ $\times 10^6$ $\psi (3686)$ decays collected with the BESIII detector at BEPCII, we report an observation of ${\Xi }^{-}$ transverse polarization with…