Measurements of the absolute branching fractions of ${\Omega }^{-}$ decays and test of the $\Delta I=1/2$ rule

Abstract

Based on a data set of $(27.12\pm 0.10)\times 10^8$ $\psi (3686)$ events collected at the BESIII experiment, the absolute branching fractions of the three dominant ${\Omega }^{-}$ decays are measured to be ${\mathcal{B}}_{{\Omega }^{-}\to {\Xi }^0{\pi }^{-}}=(25.03\pm 0.44\pm 0.53)\%$, ${\mathcal{B}}_{{\Omega }^{-}\to {\Xi }^{-}{\pi }^0}=(8.43\pm 0.52\pm 0.28)\%$, and ${\mathcal{B}}_{{\Omega }^{-}\to \Lambda K^{-}}=(66.3\pm 0.8\pm 2.0)\%$, where the first and second uncertainties are statistical and systematic, respectively. The ratio between ${\mathcal{B}}_{{\Omega }^{-}\to {\Xi }^0{\pi }^{-}}$ and ${\mathcal{B}}_{{\Omega }^{-}\to {\Xi }^{-}{\pi }^0}$ is determined to be $2.97\pm 0.19\pm 0.11$, which is in good agreement with the PDG value of $2.74\pm 0.15$, but greater by more than four standard deviations than the theoretical prediction of 2 obtained from the $\Delta I=1/2$ rule.

References in corpus (16)

• Design and Construction of the BESIII Detector
• Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations
• Future Physics Programme of BESIII
• Kaon Decays in the Standard Model
• Method for detector description transformation to Unity and application in BESIII
• Branching fraction measurements of χ_{c0} and χ_{c2} to π^0π^0 and ηη
• Determination of the number of $\psi (3686)$ events at BESIII
• Measurement of $e^{+}{e}^{-}\to K^{+}{K}^{-}$ cross section at $\sqrt{s}=2.00-3.08$ GeV
• Prospects for rare and forbidden hyperon decays at BESIII
• Study of CP violation in hyperon decays at Super Charm-Tau Factories with a polarized electron beam
• Measurement of the Spin of the Omega^- Hyperon at BABAR
• Model independent determination of the spin of the ${\Omega }^{-}$ and its polarization alignment in $\psi (3686)\to {\Omega }^{-}{\bar{\Omega }}^{+}$
• First Observation of the Decays chi_{cJ} -> pi^0 pi^0 pi^0 pi^0
• Weak Nonleptonic Omega Decay in Chiral Perturbation Theory
• |Delta I|=3/2 Decays of the Omega^- in Chiral Perturbation Theory
• The Decay Omega^- -> Xi^- pi^+ pi^- in Chiral Perturbation Theory

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