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تسجيل مستخدم جديدMeasurement of Y(5S) decays to B^0 and B^+ mesons
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A. Drutskoy
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Decays of the Y(5S) resonance to channels with B^+ and B^0 mesons are studied using a 23.6 fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric-energy e^+ e^- collider. Fully reconstructed B^+ -> J/psi K^+, B^0 -> J/psi K^{*0}, B^+ -> bar{D}^0 pi^+ and B^0 -> D^- pi^+ decays are used to obtain the charged and neutral B production rates per bbar{b} event, f(B^+) = (72.1 ^{+3.9}_{-3.8} pm 5.0)% and f(B^0) = (77.0 ^{+5.8}_{-5.6} pm 6.1)%. Assuming equal rates to B^+ and B^0 mesons in all channels produced at the Y(5S) energy, we measure the fractions for transitions to two-body and three-body channels with B meson pairs, f(Bbar{B}) = (5.5 ^{+1.0}_{-0.9} pm 0.4)%, f(Bbar{B}^* + B^*bar{B}) = (13.7 pm 1.3 pm 1.1)%, f(B^*bar{B}^*) = (37.5 ^{+2.1}_{-1.9} pm 3.0)%, f(Bbar{B}pi) = (0.0 pm 1.2 pm 0.3)%, f(Bbar{B}^*pi + B^*bar{B}pi) = (7.3 ^{+2.3}_{-2.1} pm 0.8)%, and f(B^*bar{B}^*pi) = (1.0 ^{+1.4}_{-1.3} pm 0.4)%. The latter three fractions are obtained assuming isospin conservation.
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Decays of the Y(5S) resonance to channels with B^+ and B^0 mesons are studied using a 23.6 fb^-1 data sample collected on the Y(5S) resonance with the Belle detector at the KEKB asymmetric energy e^+ e^- collider. The fully reconstructed B^+ -> J/psi
K^+, B^0 -> J/psi K^{*0}, B^+ -> bar_D^0 pi^+ and B^0 -> D^- pi^+ decays are used to obtain the B^+ and B^0 production rates per bb_bar event, f(B^+) = (67.5 pm 3.6 pm 4.8)% and f(B^0)=(70.4^{+5.2}_{-5.1} pm 6.2)%$. Assuming equal rates to B^+ and B^0 mesons in all channels produced at the Y(5S) energy, we measure the fractions for bb_bar event transitions to the two-body and multi-body channels with B^{+/0} meson pairs, f(Bbar{B}) = (5.1 pm 0.9 pm 0.4)%, f(Bbar{B}^*+B^*bar{B}) = (12.6^{+1.2}_{-1.1} pm 1.0)%, f(B^*bar{B}^*) = (34.5^{+1.9}_{-1.8} pm 2.7)%, f(B^{(*)}bar{B}^{(*)}pi(pi)) = (16.4^{+1.6}_{-1.5} pm 1.2)%, f(Bbar{B} pi) = (0.0 pm 1.1 pm 0.2)%, f(Bbar{B}^*pi+B^*bar{B}pi) = (6.8^{+2.1}_{-2.0} pm 0.7)%, and f(B^*bar{B}^*pi) = (1.0^{+1.3}_{-1.2} pm 0.3)%.
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