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arXiv · 0904.4724

Measurement of the Branching Fraction and Lambda-bar Polarization in B0 -> Lambda-bar p pi-

The BABAR Collaboration·B. Aubert
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Abstract

We present a measurement of the B0 --> Lambda-bar p pi- branching fraction performed using the BaBar detector at the PEP-II asymmetric e+e- collider. Based on a sample of 467 million BB-bar pairs we measure B(B0 --> Lambda-bar p pi-) = [3.07 pm 0.31 (stat.) pm 0.23 (syst.)] x 10^{-6}. The measured differential spectrum as a function of the dibaryon invariant mass m(Lambda p) shows a near-threshold enhancement similar to that observed in other baryonic B decays. We study the Lambda-bar polarization as a function of Lambda-bar energy in the B0 rest frame (E*_Lambda) and compare it with theoretical expectations of fully longitudinally right-polarized Lambda-bar at large E*_Lambda.

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The BABAR Collaboration, B. Aubert. 2009-07-10. Measurement of the Branching Fraction and Lambda-bar Polarization in B0 -> Lambda-bar p pi-. https://doi.org/10.1103/physrevd.79.112009

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