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arXiv · hep-ph/9506255

The asymptotic behaviour of the $π^0$ $γ^\ast$ $γ^\ast$ vertex

J. -M. Gérard·T. Lahna
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Abstract

The Bjorken-Johnson-Low theorem applied to the $γ^\ast \to γ^\ast π^0$ process provides us with a rather remarkable asymptotic behaviour for the $π^0 γ^\ast γ^\ast$ vertex. We compare our result with previous QCD- inspired estimates and argue that the predicted behaviour is quite consistent with the present data on hadronic $J/Ψ$ decays and ensures the matching of long- and short-distance radiative corrections to $π^+ \to e^+ ν_e$.

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J. -M. Gérard, T. Lahna. 1995-06-07. The asymptotic behaviour of the $π^0$ $γ^\ast$ $γ^\ast$ vertex. https://doi.org/10.1016/0370-2693(95)00811-x

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