اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the Resonant and Non-Resonant Branching Ratios in $Xi_{c}^{0} rightarrow Xi^{0} K^+ K^-$
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Using the entire data sample of $980$ $fb^{-1}$ integrated luminosity collected with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider, we present an amplitude analysis measuring the branching fractions of the Cabibbo-allowed, $W$-exchange resonant decay $Xi_{c}^{0} rightarrow Xi^{0} phi (to K^+ K^-)$ with a polarized $phi$ and the non-resonant decay via a direct process $Xi_{c}^{0} rightarrow Xi^{0} K^+ K^-$. We present these measurements, relative to the normalization mode $Xi^{-}pi^{+}$, and find branching ratios $frac{mathcal{B}(Xi_{c}^{0} rightarrow Xi^{0} phi (rightarrow K^{+}K^{-}))}{mathcal{B}(Xi_{c}^{0} rightarrow Xi^{-} pi^{+})} = 0.036 pm 0.004 (stat.) pm 0.002 (syst.)$ and $frac{mathcal{B}(Xi_{c}^{0} rightarrow Xi^{0} K^{+} K^{-})}{mathcal{B}(Xi_{c}^{0} rightarrow Xi^{-} pi^{+})} = 0.039 pm 0.004 (stat.) pm 0.002 (syst.)$ which suggest that only minor cusping peaks occur in the combinatorial background of $Omega^{*-} to Xi^{0}K^{-}$ due to these $Xi_{c}^{0}$ decays.
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