Observation of the $\Omega$(2012) baryon at the LHC

Abstract

A signal consistent with the $\Omega$(2012) baryon has been observed with a significance of $15\sigma$ in pp collisions at $\sqrt{s}=13$ TeV at the LHC. In this paper, the analysis technique is described and measurements of the mass and width of the $\Omega$(2012) are reported, along with the first measurement of its transverse-momentum spectrum and yield. This paper corroborates the observation by Belle of this excited $\Omega$ state and the observation that the $\Omega$(2012) has a rather narrow width for a strongly decaying resonance. The yield measurement is combined with a statistical thermal model calculation of strange baryon yield ratios to obtain estimates of the $\Omega {(2012)}^{-}\to \Xi \overline{\mathrm{K}}$ branching ratios. These results will improve our understanding of the internal structure and mass spectrum of excited baryon states and serve as a baseline for searches regarding modifications of these properties in high-temperature media.

30 pages, 4 captioned figures, 2 tables, authors from page 24, figures at http://alice-publications.web.cern.ch/node/11891

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Cited by in corpus (1)

• Radiative decays of the $\Omega (2012)$ as a hadronic molecule