اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of $B^0 to J/psi eta^{(}{}{}^{)}$ and Constraint on the $eta-eta$ Mixing Angle
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We measure the branching fractions of $B^{0} to J/psi eta^{(}{}{}^{)}$ decays with the complete Belle data sample of $772 times 10^{6}$ $Bbar{B}$ events collected at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. The results for the branching fractions are: ${cal B}(B^{0} to J/psi eta)=(12.3 pm ^{1.8}_{1.7} pm 0.7) times 10^{-6}$ and ${cal B}(B^{0} to J/psieta) < 7.4 times 10^{-6}$ at 90% confidence level. The $eta-eta$ mixing angle is constrained to be less than $ 42.2^{circ}$ at 90% confidence level.
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