Observation of the ${\Lambda }_{\text{b}}^0$ $\to$ J/$\psi {\Xi }^{-}$K${}^{+}$ decay

Abstract

Using proton-proton collision data corresponding to an integrated luminosity of 140 fb${}^{-1}$ collected by the CMS experiment at $\sqrt{s}$ = 13 TeV, the ${\Lambda }_{\text{b}}^0$ $\to$ J/$\psi {\Xi }^{-}$K${}^{+}$ decay is observed for the first time, with a statistical significance exceeding 5 standard deviations. The relative branching fraction, with respect to the ${\Lambda }_{\text{b}}^0$ $\to$ $\psi$(2S)$\Lambda$ decay, is measured to be $\mathcal{B}$(${\Lambda }_{\text{b}}^0$ $\to$ J/$\psi {\Xi }^{-}$K${}^{+}$) / $\mathcal{B}$( ${\Lambda }_{\text{b}}^0$ $\to$ $\psi$(2S)$\Lambda$) = [3.38 $\pm$ 1.02 $\pm$ 0.61 $\pm$ 0.03]%, where the first uncertainty is statistical, the second is systematic, and the third is related to the uncertainties in $\mathcal{B}$($\psi$(2S) $\to$ J/$\psi {\pi }^{+}{\pi }^{-}$) and $\mathcal{B}$(${\Xi }^{-}$ $\to$ $\Lambda {\pi }^{-}$).

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/BPH-22-002 (CMS Public Pages)

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Cited by in corpus (3)

• Production mechanism of hidden-charm pentaquark states $P_{c\bar{c}s}$ with strangeness $S=-1$
• Triple-strangeness hidden-charm pentaquarks
• Observation of the ${\Lambda }_b^0\to J/\psi {\Xi }^{-}{K}^{+}$ and ${\Xi }_b^0\to J/\psi {\Xi }^{-}{\pi }^{+}$ decays