Decays of the Ξ_b^- and Ω_b^- baryons to the charmless final states ph^-h^'-, where h^(') denotes a kaon or pion, are searched for with the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb^-1. The decay Ξ_b^-→pK^-K^- is observed with a significance of 8.7 standard deviations, and evidence at the level of 3.4 standard deviations is found for the Ξ_b^-→pK^-π^- decay. Results are reported, relative to the B^-→K^+K^-K^- normalization channel, for the products of branching fractions and b-hadron production fractions. The branching fractions of Ξ_b^-→pK^-π^- and Ξ_b^-→pπ^-π^- relative to Ξ_b^-→pK^-K^- decays are also measured.
Observation of the Decay Ξ_b^-→pK^-K^-
Veltri, M;
2017
Abstract
Decays of the Ξ_b^- and Ω_b^- baryons to the charmless final states ph^-h^'-, where h^(') denotes a kaon or pion, are searched for with the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb^-1. The decay Ξ_b^-→pK^-K^- is observed with a significance of 8.7 standard deviations, and evidence at the level of 3.4 standard deviations is found for the Ξ_b^-→pK^-π^- decay. Results are reported, relative to the B^-→K^+K^-K^- normalization channel, for the products of branching fractions and b-hadron production fractions. The branching fractions of Ξ_b^-→pK^-π^- and Ξ_b^-→pπ^-π^- relative to Ξ_b^-→pK^-K^- decays are also measured.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
