Measurement of the branching fraction and Λ̄ polarization in B0→Λ̄pπ-

We present a measurement of the B0→Λ̄pπ- branching fraction performed using the BABAR detector at the PEP-II asymmetric e+e- collider. Based on a sample of 467×106 BB̄ pairs we measure B(B0→Λ̄pπ-)=[3.07±0.31(stat)±0.23(syst)] ×10-6. The measured differential spectrum as a function of the dibaryon in...

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Bibliographic Details
Main Authors: Aubert, B, Karyotakis, Y, Lees, J, Poireau, V, Prencipe, E, Prudent, X, Tisserand, V, Garra Tico, J, Grauges, E, Martinelli, M, Palano, A, Pappagallo, M, Eigen, G, Stugu, B, Sun, L, Battaglia, M, Brown, D, Kerth, LT, Kolomensky, Y, Lynch, G, Osipenkov, I, Tackmann, K, Tanabe, T, Hawkes, C, Soni, N
Format: Journal article
Language:English
Published: 2009
Description
Summary:We present a measurement of the B0→Λ̄pπ- branching fraction performed using the BABAR detector at the PEP-II asymmetric e+e- collider. Based on a sample of 467×106 BB̄ pairs we measure B(B0→Λ̄pπ-)=[3.07±0.31(stat)±0.23(syst)] ×10-6. The measured differential spectrum as a function of the dibaryon invariant mass m(Λ̄p) shows a near-threshold enhancement similar to that observed in other baryonic B decays. We study the Λ̄ polarization as a function of Λ̄ energy in the B0 rest frame (EΛ̄*) and compare it with theoretical expectations of fully longitudinally right-polarized Λ̄ at large EΛ̄*. © 2009 The American Physical Society.