Study of the rare hyperon decay Omega \to Xi π^+ π^-

HyperCP Collaboration; O. Kamaev; N. Solomey; R. A. Burnstein; A. Chakravorty; Y. C. Chen; W. -S. Choong; K. Clark; E. C. Dukes; C. Durandet; J. Felix; Y. Fu; G. Gidal; H. R. Gustafson; T. Holmstrom; M. Huang; C. James; C. M. Jenkins; T. D. Jones; D. M. Kaplan; M. J. Longo; L. C. Lu; W. Luebke; K. -B. Luk; K. S. Nelson; H. K. Park; J. -P. Perroud; D. Rajaram; H. A. Rubin; J. Volk; C. G. White; S. L. White; P. Zyla

doi:10.1016/j.physletb.2010.08.037

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arXiv · 1008.4405

Study of the rare hyperon decay Omega \to Xi π^+ π^-

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Abstract

We report a new measurement of the decay Ω^- \to Ξ^- π^+ π^- with 76 events and a first observation of the decay Ω^+ \to Ξ^+ π^+ π^- with 24 events, yielding a combined branching ratio (3.74 ^{+0.67}_{-0.56}) \times 10^{-4}. This represents a factor 25 increase in statistics over the best previous measurement. No evidence is seen for CP violation, with B(Ω^- \to Ξ^- π^+ π^-)=4.04^{+0.83}_{-0.71} \times 10^{-4} and B(Ω^+ \to Ξ^+ π^+ π^-)=3.15^{+1.12}_{-0.89} \times 10^{-4}. Contrary to theoretical expectation, we see little evidence for the decays Ω^- \to Ξ_{1530}^{*0} π^- and Ω^+ \to Ξ_{1530}^{*0} π^+ and place a 90% C.L. upper limit on the combined branching ratio B(Ω^-(Ω^+) \to Ξ^{*0}_{1530}(Ξ^{*0}_{1530}) π^\mp)<7.0 \times 10^{-5}.

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HyperCP Collaboration, O. Kamaev, N. Solomey, R. A. Burnstein, A. Chakravorty, Y. C. Chen, W. -S. Choong, K. Clark, E. C. Dukes, C. Durandet, J. Felix, Y. Fu, G. Gidal, H. R. Gustafson, T. Holmstrom, M. Huang, C. James, C. M. Jenkins, T. D. Jones, D. M. Kaplan, M. J. Longo, L. C. Lu, W. Luebke, K. -B. Luk, K. S. Nelson, H. K. Park, J. -P. Perroud, D. Rajaram, H. A. Rubin, J. Volk, C. G. White, S. L. White, P. Zyla. 2010-08-25. Study of the rare hyperon decay Omega \to Xi π^+ π^-. https://doi.org/10.1016/j.physletb.2010.08.037

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