اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدStudy of the rare hyperon decay Omega to Xi pi^+ pi^-
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We report a new measurement of the decay Omega^- to Xi^- pi^+ pi^- with 76 events and a first observation of the decay Omega^+ to Xi^+ pi^+ pi^- with 24 events, yielding a combined branching ratio (3.74 ^{+0.67}_{-0.56}) times 10^{-4}. This represents a factor 25 increase in statistics over the best previous measurement. No evidence is seen for CP violation, with B(Omega^- to Xi^- pi^+ pi^-)=4.04^{+0.83}_{-0.71} times 10^{-4} and B(Omega^+ to Xi^+ pi^+ pi^-)=3.15^{+1.12}_{-0.89} times 10^{-4}. Contrary to theoretical expectation, we see little evidence for the decays Omega^- to Xi_{1530}^{*0} pi^- and Omega^+ to Xi_{1530}^{*0} pi^+ and place a 90% C.L. upper limit on the combined branching ratio B(Omega^-(Omega^+) to Xi^{*0}_{1530}(Xi^{*0}_{1530}) pi^mp)<7.0 times 10^{-5}.
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