Observation of the Ω(2012) baryon at the LHC

Abstract

A signal consistent with the Omega(2012) baryon has been observed with a significance of 15s in pp collisions at root 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 transversemomentum spectrum and yield. This paper corroborates the observation by the Belle Collaboration 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)(-) -> Xi(K) over bar 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.