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arXiv · 0907.1776

Observation and Polarization Measurement of B0 --> a1(1260)+ a1(1260)- Decay

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of the branching fraction B and the longitudinal polarization fraction fL for B0 -> a1(1260)+ a1(1260)- decays, with a1(1260)+/- -> π- π+ π+/-. The data sample, collected with the detector BaBar at the SLAC National Accelerator Laboratory, represents 465 10^6 produced BBbar pairs. We measure B(B0 -> a1(1260)+ a1(1260)-) x [B(a1(1260)+ -> π- π+ π+)]^2 = (11.8 \pm 2.6 \pm 1.6) 10^{-6} and fL = 0.31 \pm 0.22 \pm 0.10, where the first uncertainty is statistical and the second systematic. The decay mode is measured with a significance of 5.0 standard deviations including systematic uncertainties.

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The BABAR Collaboration, B. Aubert. 2009-07-10. Observation and Polarization Measurement of B0 --> a1(1260)+ a1(1260)- Decay. https://doi.org/10.1103/physrevd.80.092007

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