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Extracting Br(omega->pi^+ pi^-) from the Time-like Pion Form-factor

S. Gardner·H. B. O'Connell
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Abstract

We extract the G-parity-violating branching ratio Br(omega->pi^+ pi^-) from the effective rho-omega mixing matrix element Pi_{rho omega}(s), determined from e^+e^- -> pi^+ pi^- data. The omega->pi^+ pi^- partial width can be determined either from the time-like pion form factor or through the constraint that the mixed physical propagator D_{rho omega}^{mu nu}(s) possesses no poles. The two procedures are inequivalent in practice, and we show why the first is preferred, to find finally Br(omega->pi^+ pi^-) = 1.9 +/- 0.3%.

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S. Gardner, H. B. O'Connell. 1999-03-04. Extracting Br(omega->pi^+ pi^-) from the Time-like Pion Form-factor. https://doi.org/10.1103/physrevd.59.076002

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