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arXiv · 0806.2992

The anomalous Upsilon(1S)pi+pi- and Upsilon(2S)pi+pi- production near the Upsilon(5S) resonance

K. -F. Chen
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Abstract

We report the study of e+e- -> Upsilon(1S)pi+pi-, Upsilon(2S)pi+pi-, Upsilon(3S)pi+pi-, and Upsilon(1S)K+K-, near the peak of the Upsilon(5S) resonance. The results are based on a data sample of 21.7 fb^-1 collected with the Belle detector at the KEKB e+e- collider. Attributing the signals to the Upsilon(5S) resonance, the partial widths Gamma(Upsilon(5S)->Upsilon(1S)pi+pi-) = 0.59+-0.04(stat)+-0.09(syst) MeV and Gamma(Upsilon(5S)->Upsilon(2S)pi+pi-) = 0.85+-0.07(stat)+-0.16(syst) MeV are obtained from the observed cross sections. These values exceed by more than two orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.

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K. -F. Chen. 2008-06-18. The anomalous Upsilon(1S)pi+pi- and Upsilon(2S)pi+pi- production near the Upsilon(5S) resonance. https://arxiv.org/abs/0806.2992

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