Study of the decay B̅[superscript 0]→Λ[+ over c]p̅π[superscript +]π[superscript -] and its intermediate states

Abstract

We study the decay B̅[superscript 0]→Λ[+ over c]p̅π[superscript +]π[superscript -], reconstructing the Λ[+ over c] baryon in the pK[superscript -]π[superscript +] mode, using a data sample of 467×10[superscript 6] BB̅ pairs collected with the BABAR detector at the PEP-II storage rings at SLAC. We measure branching fractions for decays with intermediate Σ[subscript c] baryons to be B[B̅[superscript 0]→Σ[subscript c](2455)[superscript ++]p̅π[superscript -]]=(21.3±1.0±1.0±5.5)×10[superscript -5], B[B̅[superscript 0]→Σ[subscript c](2520)[superscript ++]p̅ π[superscript -]]=(11.5±1.0±0.5±3.0)×10[superscript -5], B[B̅[superscript 0]→Σ[subscript c](2455)[superscript 0]p̅ π[superscript +]]=(9.1±0.7±0.4±2.4)×10[superscript -5], and B[B̅[superscript 0]→Σ[subscript c](2520)[superscript 0]p̅π[superscript +]]=(2.2±0.7±0.1±0.6)×10[superscript -5], where the uncertainties are statistical, systematic, and due to the uncertainty on the Λ[+ over c]→pK[superscript -]π[superscript +] branching fraction, respectively. For decays without Σ[subscript c](2455) or Σ[subscript c](2520) resonances, we measure B[B̅[superscript 0]→Λ[+ over c]p̅π[superscript +]π[superscript -]][subscript non-Σc]= (79±4±4±20)×10[superscript -5]. The total branching fraction is determined to be B[B̅[superscript 0]→Λ[+ over c]p̅π[superscript +]π[superscript -]][subscript total]=(123±5±7±32)×10[superscript -5]. We examine multibody mass combinations in the resonant three-particle Σ[subscript c]p̅ π final states and in the four-particle Λ[+ over c]p̅π[superscript +]π[superscript -] final state, and observe different characteristics for the p̅ π combination in neutral versus doubly charged Σ[subscript c] decays.