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تسجيل مستخدم جديدSearch for $B^0$ Decays to Invisible Final States ($+gamma$) at Belle
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We report searches for $B^0torm{invisible}$ and $B^0torm{invisible}+gamma$ decays, where the energy of the photon is required to be larger than 0.5 GeV. These results are obtained from a $711,{rm fb}^{-1}$ data sample that contains $772 times 10^6 Bbar{B}$ pairs and was collected near the $Upsilon,(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. We observe no significant signal for either decay and set upper limits on their branching fractions at $90%$ confidence level of $mathcal{B},(B^0torm{invisible}) < 7.8times10^{-5}$ and $mathcal{B},(B^0torm{invisible}+gamma) < 1.6times10^{-5}$.
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