CMS-PAS-BPH-19-002

CMS-PAS-BPH-19-002
Observation of the $\Lambda_{\mathrm{b}} \to \mathrm{J}/\psi \Lambda \phi$ decay in proton-proton collisions at $\sqrt{s}=$ 13 TeV
CMS Collaboration
August 2019

Abstract: We report a first observation of the $\Lambda_{\mathrm{b}} \to \mathrm{J}/\psi \Lambda \phi$ decay using proton-proton collision data collected at $\sqrt{s}$ = 13 TeV by the CMS experiment at the LHC, and corresponding to an integrated luminosity of 60 fb $^{-1}$ . The ratio of the branching fractions ${\cal B}(\Lambda_{\mathrm{b}} \to \mathrm{J}/\psi \Lambda \phi)/{\cal B}(\Lambda_{\mathrm{b}}\to \psi\mathrm{(2S)} \Lambda)$ is measured to be (8.26 $\pm$ 0.90 (stat) $\pm$ 0.68 (syst) $\pm$ 0.11 ( ${\cal B}$ ) ) $\times 10^{-2}$ , where the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainties in the world-average branching fractions.
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; These preliminary results are superseded in this paper, PLB 802 (2020) 135203. The superseded preliminary plots can be found here.

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