اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the branching fraction for $B^{0} rightarrow pi^{0} pi^{0}$ decays reconstructed in 2019-2020 Belle II data
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We report the first reconstruction of the $B^{0} to pi^{0} pi^{0}$ decay mode at Belle II using samples of 2019 and 2020 data that correspond to 62.8 fb$^{-1}$ of integrated luminosity. We find $14.0^{+6.8}_{-5.6}$ signal decays, corresponding to a significance of 3.4 standard deviations and determine a branching ratio of $mathcal{B}(B^{0} rightarrow pi^{0} pi^{0}) = [0.98^{+0.48}_{-0.39} pm 0.27] times 10^{-6}$. The results agree with previous determinations and contribute important information to an early assessment of detector performance and Belle IIs potential for future determinations of $alpha/phi_2$ using $B rightarrow pi pi$ modes.
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