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Analysis of rho-omega interference in the pion form-factor

K. Maltman·H. B. O'Connell·A. G. Williams
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Abstract

The formalism underlying the analysis of e+e- -> pi+pi- in the rho-omega interference region is carefully revisited. We show that the standard neglect of the pure I=0 omega, omega_I, `direct'' coupling to pi-pi is not valid, and extract those combinations of the direct coupling and ρ-omega mixing allowed by experiment. The latter is shown to be only very weakly constrained by experiment, and we conclude that data from the e+e- -> pi+pi- interference region cannot be used to fix the value of rho-omega mixing in a model-independent way unless the errors on the experimental phase can be significantly reduced. Certain other modifications of the usual formalism necessitated by the unavoidable momentum-dependence of rho-omega mixing are also discussed.

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K. Maltman, H. B. O'Connell, A. G. Williams. 1996-08-19. Analysis of rho-omega interference in the pion form-factor. https://doi.org/10.1016/0370-2693(96)00293-6

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