اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the form factors in the decay $D^+ to omega e^+ u_{e}$ and search for the decay $D^+ to phi e^+ u_{e}$
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Using 2.92 fb$^{-1}$ of electron-positron annihilation data collected at a center-of-mass energy of $sqrt{s}= 3.773$ GeV with the BESIII detector, we present an improved measurement of the branching fraction $mathcal{B}(D^+ to omega e^+ u_{e}) = (1.63pm0.11pm0.08)times 10^{-3}$. The parameters defining the corresponding hadronic form factor ratios at zero momentum transfer are determined for the first time, we measure them to be $r_V = 1.24pm0.09pm0.06$ and $r_2 = 1.06pm0.15 pm 0.05$. The first and second uncertainties are statistical and systematic, respectively. We also search for the decay $D^+ to phi e^+ u_{e}$. An improved upper limit $mathcal{B}(D^+ to phi e^+ u_{e}) < 1.3 times 10^{-5}$ is set at 90% confidence level.
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In an analysis of a 2.92~fb$^{-1}$ data sample taken at 3.773~GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be $mathcal B(D^0 to K^-e^+ u_e)=(3.505pm 0.014 pm 0.033)%$ and $mathcal
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