اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدSearch for the reaction channel $e^+e^- rightarrow eta_ceta pi^+pi^-$ at center-of-mass energies from 4.23 to 4.60 GeV
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Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider, we search for the process $e^+e^-rightarrow eta_ceta pi^+pi^-$. The search is performed using five large data sets recorded at center-of-mass energies of 4.23, 4.26, 4.36, 4.42, and 4.60 GeV. The $eta_c$ meson is reconstructed in 16 exclusive decay modes. No signal is observed in the $eta_c$ mass region at any center-of-mass energy. The upper limits on the reaction cross sections are determined to be 6.2, 10.8, 27.6, 22.6 and 23.7 pb at the 90% confidence level at the center-of-mass energies listed above.
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