Light hyperon polarization and CP test at BESIII

Abstract

Hyperon is an ideal probe to study the QCD in the region of non-perturbative to perturbative. Using 1.31 × 109 J/ψ and 448.1 × 106 ψ(3686) events, the hyperon anti-hyperon pair production are well studied. The hyperon polarization and its decay parameter have been measured in high precision through their quantum entangle system. By comparing the decay parameters in hyperon and anti-hyperon decays, the CP conservation observables has been measured which is important to test the Standard Model and search for New Physics.