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تسجيل مستخدم جديدSearch for transitions from $Upsilon(4S)$ and $Upsilon(5S)$ to $eta_b(1S)$ and $eta_b(2S)$ with emission of an $omega$ meson
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Using data collected in the Belle experiment at the KEKB asymmetric-energy $e^+e^-$ collider we search for transitions $Upsilon(4S) rightarrow eta_b(1S)omega$, $Upsilon(5S) rightarrow eta_b(1S)omega$ and $Upsilon(5S) rightarrow eta_b(2S)omega$. No significant signals are observed and we set 90% confidence level upper limits on the corresponding visible cross sections: $0.2 ~textrm{pb}, 0.4 ~textrm{pb}$ and $1.9 ~textrm{pb}$, respectively.
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