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تسجيل مستخدم جديدA study of $rho-omega$ mixing in resonance chiral theory
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The strong and electromagnetic corrections to $rho-omega$ mixing are calculated using a SU(2) version of resonance chiral theory up to next-to-leading orders in $1/N_C$ expansion, respectively. Up to our accuracy, the effect of the momentum dependence of $rho-omega$ mixing is incorporated due to the inclusion of loop contributions. We analyze the impact of $rho-omega$ mixing on the pion vector form factor by performing numerical fit to the data extracted from $e^+e^-rightarrow pi^+pi^-$ and $taurightarrow u_{tau}2pi$, while the decay width of $omegarightarrow pi^+pi^-$ is taken into account as a constraint. It is found that the momentum dependence is significant in a good description of the experimental data. In addition, based on the fitted values of the involved parameters, we analyze the decay width of $omega rightarrow pi^+pi^-$, which turns out to be highly dominated by the $rho-omega$ mixing effect.
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