Observation of the Decay B0->rho+rho- and Measurement of the Branching Fraction and Polarization

The BABAR Collaboration; B. Aubert

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arXiv · hep-ex/0308024

Observation of the Decay B0->rho+rho- and Measurement of the Branching Fraction and Polarization

The BABAR Collaboration·B. Aubert

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Abstract

We have observed the rare decay B0->rho+rho- in a sample of 89 million BBbar pairs recorded with the BABAR detector. We measure the branching fraction B(B0->rho+rho-)=(27+7-6+5-7)10^-6 and determine the longitudinal polarization fraction Gamma_L/Gamma=0.99+0.01-0.07+-0.03. Our results are preliminary.

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The BABAR Collaboration, B. Aubert. 2003-08-09. Observation of the Decay B0->rho+rho- and Measurement of the Branching Fraction and Polarization. https://arxiv.org/abs/hep-ex/0308024

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