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تسجيل مستخدم جديدToward $e^+e^-to pi^+pi^-$ annihilation inspired by higher $rho$ mesonic states around 2.2 GeV
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Very recently, the {it BABAR} Collaboration indicated that there exist an explicit enhancement structure near 2.2 GeV when focusing on the $e^+e^-topi^+pi^-$ process again, which inspires our interest in studying the production of higher $rho$ mesonic states. Since the branching ratio of $pi^+pi^-$ channel of $D-$wave $rho$ states are much smaller than $S-$wave states, we choose $rho(1900)$ and $rho(2150)$ as the intermediate states in $e^+e^-topi^+pi^-$, where $rho(1900)$ and $rho(2150)$ are treated as $rho(3S)$ and $rho(4S)$ states, respectively. Our result indicates that the $BABAR$s data of $e^+e^-topi^+pi^-$ around 2 GeV can be depicted well, which shows that this enhancement structure near 2.2 GeV existing in $e^+e^-topi^+pi^-$ can be due to the contribution from two $rho$ mesons, $rho(1900)$ and $rho(2150)$. Additionally, this conclusion can be enforced by the consistence of the extracted values of $Gamma_{e^+e^-}mathcal{B}(pi^+pi^-)$ of $rho(1900)$ and $rho(2150)$ in the whole fitting processes and the corresponding theoretical calculations. The present study of $e^+e^-topi^+pi^-$ data may provide valuable information to establish the $rho$ meson family.
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