Abstract
Based on data samples collected with the BESIII detector at the BEPCII collider at nine center of mass energies from 4.21 to 4.42 GeV, we search for the production of (, 1, 2). The process is observed for the first time, and the Born cross sections at and 4.26 GeV are measured to be and , respectively, where the first uncertainties are statistical and the second are systematic. The signals at the other seven energies and the and signals are not significant, and the upper limits on the cross sections are determined. By examining the cross section as a function of center of mass energy, we find that it is inconsistent with the line shape of the observed in . Assuming the signals come from a single resonance, we extract the mass and width of the resonance to be and , respectively, and the statistical significance is more than .
- Received 27 October 2014
DOI:https://doi.org/10.1103/PhysRevLett.114.092003
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