اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThe omega rho pi coupling in the VMD model revisited
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We determine the value of the omega -rho- pi mesons coupling (g_{omegarhopi}), in the context of the vector meson dominance model, from radiative decays, the omega rightarrow 3pi decay width and the e^+e^- rightarrow 3pi cross section. For the last two observables we consider the effect of either a heavier resonance (rho(1450)) or a contact term. A weighted average of the results from the set of observables yields g_{omegarhopi} =14.7 pm 0.1 GeV^{-1} in absence of those contributions, and g_{omegarhopi} =11.9 pm 0.2 GeV^{-1} or g_{omegarhopi} =11.7 pm 0.1 GeV^{-1} when including the rho or contact term respectively. The inclusion of these additional terms makes the estimates from the different observables to lay in a more reduced range. Improved measurements of these observables and the rho(1450) meson parameters are needed to give a definite answer on the pertinence of the inclusion of this last one in the considered processes.
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