TY - JOUR
T1 - Observation of a New Ξ − b Resonance
AU - Aaij, R.
AU - Adeva, B.
AU - Adinolfi, M.
AU - Ajaltouni, Z.
AU - Akar, S.
AU - Albrecht, J.
AU - Alessio, F.
AU - Dufour, L.
AU - Mulder, M
AU - Onderwater, C. J. G.
AU - Pellegrino, A.
AU - Tolk, S.
AU - van Veghel, M.
AU - LHCb Collaboration
PY - 2018/8/15
Y1 - 2018/8/15
N2 - From samples of pp 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 Λ0bK− and Ξ0bπ− invariant mass spectra is observed. In the quark model, radially and orbitally excited Ξ−b resonances with quark content bds are expected. Referring to this peak as Ξb(6227)−, the mass and natural width are measured to be mΞb(6227)−=6226.9±2.0±0.3±0.2 MeV/c2 and ΓΞb(6227)−=18.1±5.4±1.8 MeV/c2, where the first uncertainty is statistical, the second is systematic, and the third, on mΞb(6227)−, is due to the knowledge of the Λ0b baryon mass. Relative production rates of the Ξb(6227)−→Λ0bK− and Ξb(6227)−→Ξ0bπ− decays are also reported.
AB - From samples of pp 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 Λ0bK− and Ξ0bπ− invariant mass spectra is observed. In the quark model, radially and orbitally excited Ξ−b resonances with quark content bds are expected. Referring to this peak as Ξb(6227)−, the mass and natural width are measured to be mΞb(6227)−=6226.9±2.0±0.3±0.2 MeV/c2 and ΓΞb(6227)−=18.1±5.4±1.8 MeV/c2, where the first uncertainty is statistical, the second is systematic, and the third, on mΞb(6227)−, is due to the knowledge of the Λ0b baryon mass. Relative production rates of the Ξb(6227)−→Λ0bK− and Ξb(6227)−→Ξ0bπ− decays are also reported.
KW - HEAVY-BARYON SPECTROSCOPY
KW - DIQUARK PICTURE
KW - QUARK-MODEL
KW - DECAY
U2 - 10.1103/PhysRevLett.121.072002
DO - 10.1103/PhysRevLett.121.072002
M3 - Article
C2 - 30169090
SN - 0031-9007
VL - 121
JO - Physical Review Letters
JF - Physical Review Letters
IS - 7
M1 - 072002
ER -