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arXiv · 0808.4142

Observation of the doubly strange b baryon Omega_b-

D0 Collaboration·V. Abazov
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Abstract

We report the observation of the doubly strange b baryon Omega_b- in the decay channel Omega_b- to J/psi Omega-, with J/psi to mu+ mu- and Omega- to Lambda K-, in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV. Using approximately 1.3 fb$^{-1}$ of data collected with the D0 detector at the Fermilab Tevatron Collider, we observe 17.8 +/- 4.9 (stat) +/- 0.8 (syst) Omega_b- signal events at a mass of 6.165 +/- 0.010 (stat) +/- 0.013(syst.) GeV. The significance of the observed signal is 5.4 sigma, corresponding to a probability of 6.7 x 10^{-8} of it arising from a background fluctuation.

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D0 Collaboration, V. Abazov. 2008-12-08. Observation of the doubly strange b baryon Omega_b-. https://doi.org/10.1103/physrevlett.101.232002

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