# metadata.dc.description.abstract[].value
From samples of p p collision data collected by the LHCb experiment at √ s = 7 , 8 and 13 TeV, corresponding to integrated luminosities of 1.0, 2.0 and 1.5     fb − 1 , respectively, a peak in both the Λ 0 b K − and Ξ 0 b π − invariant mass spectra is observed. In the quark model, radially and orbitally excited Ξ − b resonances with quark content b d s are expected. Referring to this peak as Ξ b ( 6227 ) − , the mass and natural width are measured to be m Ξ b ( 6227 ) − = 6226.9 ± 2.0 ± 0.3 ± 0.2     MeV / c 2 and Γ Ξ b ( 6227 ) − = 18.1 ± 5.4 ± 1.8     MeV / c 2 , where the first uncertainty is statistical, the second is systematic, and the third, on m Ξ b ( 6227 ) − , is due to the knowledge of the Λ 0 b baryon mass. Relative production rates of the Ξ b ( 6227 ) − → Λ 0 b K − and Ξ b ( 6227 ) − → Ξ 0 b π − decays are also reported.

# metadata.dc.rights[].value
cc by (c) CERN; LHCb Collaboration, 2018

# metadata.dc.source[].value
Articles publicats en revistes (Física Quàntica i Astrofísica)