اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the branching fraction ${cal B}(bar B^0to D^{*+}ell^-bar u_ell)$ with early Belle II data
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We measure the branching fractions for the decays $bar{B}^0 to D^{*+} e^{-} bar{ u}_e$ and $bar{B}^0 to D^{*+} mu^{-} bar{ u}_mu$ using $8.70 pm 0.09~{rm fb}^{-1}$ of data collected by the Belle II experiment at the SuperKEKB asymmetric-energy $e^+ e^-$ collider. Candidate signal decays are reconstructed with the subsequent decays $D^{*+}to D^0 pi^+$ and $D^0to K^-pi^+$. We obtain the results ${cal B}(bar{B}^0 to D^{*+} e^{-} bar{ u}_e)$ = $(4.55pm0.14(mathrm{stat})pm0.35 (mathrm{syst})) %$ and ${cal B}(bar{B}^0 to D^{*+} mu^{-} bar{ u}_mu)$ = $(4.84pm 0.13(mathrm{stat})pm0.37(mathrm{syst})) %$, in agreement with the world averages. The measurements serve to validate the full chain of detector operation and calibration, data collection and processing, and production of physics results in the case of semileptonic $B$-meson decays.
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