Abellan Beteta, CarlosCalvo Gómez, MíriamCamboni, AlessandroComerma Montells, AlbertDomingo Bonal, FrancescGarrido Beltrán, LluísGraciani Díaz, RicardoGraugés Pous, EugeniLópez Asamar, EliasPérez-Calero Yzquierdo, AntonioPicatoste Olloqui, EduardoPotterat, CédricRives Molina, Vicente JoséRuiz, Hugo (Ruiz Pérez)Vázquez Gómez, RicardVilasis-Cardona, XavierLHCb Collaboration2019-05-172019-05-172013-05-020031-9007https://hdl.handle.net/2445/133354Bottom baryons decaying to a J / ψ meson and a hyperon are reconstructed using 1.0     fb − 1 of data collected in 2011 with the LHCb detector. Significant Λ 0 b → J / ψ Λ , Ξ − b → J / ψ Ξ − and Ω − b → J / ψ Ω − signals are observed and the corresponding masses are measured to be M ( Λ 0 b ) = 5619.53 ± 0.13 ( stat . ) ± 0.45 ( syst . )     MeV / c 2 , M ( Ξ − b ) = 5795.8 ± 0.9 ( stat . ) ± 0.4 ( syst . )     MeV / c 2 , M ( Ω − b ) = 6046.0 ± 2.2 ( stat . ) ± 0.5 ( syst . )     MeV / c 2 , while the differences with respect to the Λ 0 b mass are M ( Ξ − b ) − M ( Λ 0 b ) = 176.2 ± 0.9 ( stat . ) ± 0.1 ( syst . )     MeV / c 2 , M ( Ω − b ) − M ( Λ 0 b ) = 426.4 ± 2.2 ( stat . ) ± 0.4 ( syst . )     MeV / c 2 . These are the most precise mass measurements of the Λ 0 b , Ξ − b and Ω − b baryons to date. Averaging the above Λ 0 b mass measurement with that published by LHCb using 35     pb − 1 of data collected in 2010 yields M ( Λ 0 b ) = 5619.44 ± 0.13 ( stat . ) ± 0.38 ( syst . )     MeV / c 2 .8 p.application/pdfeng(c) American Physical Society, 2013Física de partículesExperimentsParticle physicsExperimentsinfo:eu-repo/semantics/article6289852019-05-17info:eu-repo/semantics/openAccess