Observation of excited Ω0𝑐 baryons in Ω−𝑏→Ξ+𝑐⁢𝐾−⁢𝜋− decays

The first observation of the Ω−𝑏→Ξ+𝑐⁢𝐾−⁢𝜋− decay is reported using 𝑝 𝑝 collision data at center of mass energies of 7, 8, and 13 TeV collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb−1. Four excited Ω0𝑐 baryons are observed in the Ξ+𝑐 𝐾− mass projection of the Ω−𝑏→Ξ+
𝑐⁢𝐾−⁢𝜋− decays with the significance of each exceeding five standard deviations. They coincide with the states previously observed in prompt 𝑝⁢𝑝 and 𝑒+⁢𝑒− production. Relative production rates, masses, and natural widths of the states are measured, and a test of spin hypotheses is performed. Moreover, the branching ratio of Ω−𝑏→Ξ+𝑐⁢𝐾−⁢𝜋− is measured relative to the Ω−𝑏→Ω0
𝑐⁢𝜋− decay mode and a precise measurement of the Ω−𝑏 mass of 6044.3±1.2±1.⁢1+0.19−0.22  MeV is obtained.