Projects per year
A study of excited Λ b 0 baryons is reported, based on a data sample collected in 2016–2018 with the CMS detector at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of up to 140fb −1. The existence of four excited Λ b 0 states: Λ b 0(5912) 0, Λ b 0(5920) 0, Λ b 0(6146) 0, and Λ b 0(6152) 0 in the Λ b 0π +π − mass spectrum is confirmed, and their masses are measured. The Λ b 0π +π − mass distribution exhibits a broad excess of events in the region of 6040–6100 MeV, whose origin cannot be discerned with the present data.
Bibliographical noteReplaced with the published version. Added the journal reference. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/BPH-19-003 (CMS Public Pages)