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arXiv · hep-ex/0306007

Observation of B+ -> rho+ rho0

J. Zhang·M. Nakao
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Abstract

We report the first observation of the charmless vector-vector decay process B+ ->rho+ rho0. The measurement uses a 78 fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric e+e- collider operating at the Upsilon(4S) resonance. We obtain a branching fraction of Br(B+ ->rho+ rho0)=(31.7+-7.1(stat.)+3.8-6.7(sys.))*10^{-6}. An analysis of the rho helicity-angle distributions gives a longitudinal polarization of Gamma_{L}/Gamma=(94.8+-10.6(stat.)+-2.1(sys.))%.

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J. Zhang, M. Nakao. 2003-06-03. Observation of B+ -> rho+ rho0. https://doi.org/10.1103/physrevlett.91.221801

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