Fig. 2: Polarization in and spin correlations of the \({e}^{+}{e}^{-}\to {\varXi }^{-}{\bar{\varXi }}^{+}\) reaction.
From: Probing CP symmetry and weak phases with entangled double-strange baryons
a, Polarization in the \({e}^{+}{e}^{-}\to {\varXi }^{-}{\bar{\varXi }}^{+}\) reaction. b–d, Spin correlations of the \({e}^{+}{e}^{-}\to {\varXi }^{-}{\bar{\varXi }}^{+}\) reaction. The coordinate systems \({ {\mathcal R} }_{{\Xi }}\) and \({ {\mathcal R} }_{\bar{{\Xi }}}\) of the Ξ− and \({\bar{{\Xi }}}^{+}\), respectively, are described in the text. The data points are determined independently in each bin of the Ξ− cosine scattering angle in the e+e− centre-of-momentum system. The blue curves represent the expected angular dependence obtained with the production parameters αψ and ΔΦ from the global maximum log-likelihood fit. The error bars indicate the statistical uncertainties.
