Observation of the $${\mathbf{\Lambda }}_{{{b}}}^{0}$$ → J/ψΞ−K+ Decay at CMS

The paper describes the observation of a new decay of a beauty baryon using the data collected in CMS experiments in 2016, 2017, and 2018 in proton‒proton collisions at a center-of-mass energy of 13 TeV. The study of the new decay deserves attention because its products contain a charmonium resonance and a doubly strange cascade hyperon, which opens a pathway to the search for new types of pentaquark states. The branching fraction ratio of the new decay to the normalization channel decay is measured.