Phys Rev Lett. 2025 Dec 31;135(26):261901. doi: 10.1103/3pcs-dxtn.
ABSTRACT
A search for the charmless baryonic decay B^{+}→Λ[over ¯]pp[over ¯]p is performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 5.4 fb^{-1}. The branching fraction for this decay is measured for the first time relative to that of the topologically similar decay B^{+}→J/ψK^{+}, with J/ψ→Λ[over ¯]pK^{-}. The branching fraction is measured to be B(B^{+}→Λ[over ¯]pp[over ¯]p)=(2.15±0.35±0.12±0.28)×10^{-7}, where the first uncertainty is statistical, the second is systematic, and the third arises from the uncertainty in the normalization channel branching fraction. The CP asymmetry is measured to be A_{CP}=(5.4±15.6±2.4)%, where the uncertainties are statistical and systematic. The background-subtracted invariant-mass distributions of Λ[over ¯]p and p[over ¯]p pairs exhibit pronounced enhancements at both kinematic thresholds, in contrast to a uniform phase-space distribution.
PMID:41557403 | DOI:10.1103/3pcs-dxtn