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arXiv · hep-ex/0507029

Observation of B0 Meson decays to a1(1260) pi

B. Aubert·BaBar Collaboration
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Abstract

We present preliminary measurements of the B meson decay B0 -> a1(1260)+ pi-, with a1(1260)+ --> pi+ pi+ pi-. The data were recorded with the BABAR detector at PEP II and correspond to 218 million BBbar pairs produced in e+e- annihilation through the Upsilon(4S) resonance. We find the branching fractions B(B0 -> a1(1260)+ pi-) = (40.2 +/- 3.9 +/- 3.9) x 10^-6. The fitted values of the a1(1260) parameters are m_a1 = 1.22 +/- 0.02 GeV/c^2 and Gamma_a1= 423 +/- 50 MeV/c^2

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B. Aubert, BaBar Collaboration. 2005-07-07. Observation of B0 Meson decays to a1(1260) pi. https://arxiv.org/abs/hep-ex/0507029

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