Observation of Ξ -, overlineΞ - production in e +e - anihilation

We present evidence for the production of Ξ· ^-, overlineΞ ^- in e ⁺e ^- annihilation into hadrons. Our measurements yields: 0.026 ± 0.008 (stat.) ± 0.009 (syst.) Ξ ^-, overlineΞ ^- per hadronic event at W ∼ 34 GeV. Using our previous measurements of Λ, overlineΛ and p, overlinep production we obtain the relative yields (Ξ ^-, overlineΞ ^-/(Λ, overlineΛ = 0.087 ± 0.03 ( stat.) ± 0.03 ( syst.) and (Ξ ^-, overlineΞ ^-/( p, overlinep = 0.033 ± 0.011 ( stat.) ± 0.011 ( syst.) .