Observation of anomalous upsilon(1S)pi+pi(-) and upsilon(2S)pi+pi(-) production near the upsilon(5S) resonance.
We report the first observation of e;{+}e;{-}-->Upsilon(1S)pi;{+}pi;{-}, Upsilon(2S)pi;{+}pi;{-}, and first evidence for e;{+}e;{-}-->Upsilon(3S)pi;{+}pi;{-}, Upsilon(1S)K+K-, near the peak of the Upsilon(5S) resonance at sqrt[s] approximately 10.87 GeV. 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 2 orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.
Department of Physics, National Taiwan University, Taipei.
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Hou
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Shapkin
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Sokolov
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Adachi
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Aihara
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Arinstein
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Aulchenko
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Aushev
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Balagura
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Bay
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Belous
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Bhardwaj
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Bitenc
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Bondar
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Bozek
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Bracko
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Brodzicka
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Browder
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Chang
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Chao
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Chen
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Chen
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Chistov
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Choi
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Dalseno
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Danilov
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Eidelman
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Gabyshev
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Ha
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Haba
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Hayasaka
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Hayashii
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Hazumi
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Hsiung
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Kichimi
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Kim
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Kinoshita
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Korpar
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Krizan
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Krokovny
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Kumar
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Kwon
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Lange
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Lee
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Lee
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Lesiak
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Limosani
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Lin
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Liu
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Liventsev
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Medvedeva
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Mitaroff
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Miyazaki
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Nakao
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Nishida
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Ozaki
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Park
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Park
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Pestotnik
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Sakai
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Schneider
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Schümann
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Schwanda
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Schwartz
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Senyo
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Shen
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Takasaki
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Tamai
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Tanaka
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Teramoto
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Trabelsi
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Uehara
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Ueno
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Ushiroda
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Usov
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Varner
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Vervink
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Villa
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Wang
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Wang
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Wang
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Wang
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Wang
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Watanabe
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Wedd
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Wicht
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Won
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Yamashita
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Yamauchi
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Yuan
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Yusa
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Zhang
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Zupanc