Abellan Beteta, CarlosCalvo Gómez, MíriamCamboni, AlessandroComerma Montells, AlbertDomingo Bonal, FrancescGarrido Beltrán, LluísGascón Fora, DavidGrabalosa Gándara, MarcGraciani Díaz, RicardoGraugés Pous, EugeniLópez Asamar, EliasPérez-Calero Yzquierdo, AntonioPicatoste Olloqui, EduardoPie Valls, B. (Blai)Potterat, CédricPuig Navarro, AlbertRoselló, M.Ruiz, Hugo (Ruiz Pérez)Vázquez Gómez, RicardVilasis-Cardona, XavierLHCb Collaboration2019-05-212019-05-212012-10-260031-9007https://hdl.handle.net/2445/133583Using p p collision data corresponding to 1.0     fb − 1 integrated luminosity collected by the LHCb detector, two narrow states are observed in the Λ 0 b π + π − spectrum with masses 5911.97 ± 0.12 ( stat ) ± 0.02 ( syst ) ± 0.66 ( Λ 0 b     mass )     MeV / c 2 and 5919.77 ± 0.08 ( stat ) ± 0.02 ( syst ) ± 0.66 ( Λ 0 b     mass )     MeV / c 2 . The significances of the observations are 5.2 and 10.2 standard deviations, respectively. These states are interpreted as the orbitally excited Λ 0 b baryons, Λ * 0 b ( 5912 ) and Λ * 0 b ( 5920 ) .8 p.application/pdfengcc by (c) CERN; LHCb Collaboration, 2012http://creativecommons.org/licenses/by/3.0/es/Física de partículesExperimentsParticle physicsExperimentsinfo:eu-repo/semantics/article6196222019-05-21info:eu-repo/semantics/openAccess