ep - p h / 97 07 25 3 v 1 5 J ul 1 99 7 1 On extracting the ρ − ω mixing amplitude from the pion form - factor ∗
نویسندگان
چکیده
In this paper we improve and extend a recent analysis which showed that the ρ−ω mixing amplitude cannot be unambiguously extracted from the pion electromagnetic form-factor in a model independent way. In particular, we focus on the argument that the extraction is sensitive to the presence of any intrinsic ω I → ππ coupling. Our extended analysis confirms the original conclusion, with only minor, quantitative differences. The extracted mixing amplitude is shown to be sensitive to both the intrinsic coupling ω I → ππ and to the value assumed for the mass of the ρ 0-meson.
منابع مشابه
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متن کاملExtracting the ρ − ω mixing amplitude from the pion form - factor
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