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The resonant structure of the reaction (B) over bar (0) --> J/psi pi(+)pi(-) is studied using data from 3 fb(-1) of integrated luminosity collected by the LHCb experiment, one third at 7 TeV center-of-mass energy and the remainder at 8 TeV. The invariant mass of the pi(+)pi(-) pair and three decay angular distributions are used to determine the fractions of the resonant and nonresonant components. Six interfering pi(+)pi(-) states, rho(770), f(0)(500), f(2)(1270), rho(1450), omega(782) and rho(1700), are required to give a good description of invariant mass spectra and decay angular distributions. The positive and negative charge parity fractions of each of the resonant final states are determined. The f(0)(980) meson is not seen and the upper limit on its presence, compared with the observed f(0)(500) rate, is inconsistent with a model where these scalar mesons are formed from two quarks and two antiquarks (tetraquarks) at the eight standard deviation level. In the q (q) over bar model, the absolute value of the mixing angle between the f(0)(980) and the f(0)(500) scalar mesons is limited to be less than 17 degrees at 90% confidence level.
Olivier Schneider, Aurelio Bay, Yi Zhang, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, François Fleuret, Elena Graverini, Renato Quagliani, Federico Betti, Jian Wang, Zhirui Xu, Lei Zhang, Jessica Prisciandaro, Christoph Frei, Mark Tobin, Minh Tâm Tran, Niko Neufeld, Matthew Needham, Marc-Olivier Bettler, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Cédric Potterat, Liang Sun, Pietro Marino, Luca Pescatore, Mirco Dorigo, Jean Wicht, Xiaoxue Han, Sebastiana Gianì, Liupan An, Federico Leo Redi, Chitsanu Khurewathanakul, Ilya Komarov, Plamen Hristov Hopchev, Thibaud Humair, Maxime Schubiger, Guido Andreassi, Hang Yin, Violaine Bellée, Olivier Göran Girard, Axel Kuonen, Preema Rennee Pais, Pavol Stefko, Maria Elena Stramaglia, Tommaso Colombo, Vladimir Macko, Hans Dijkstra, Gerhard Raven, Peter Clarke, Frédéric Teubert, Adam Davis, Paolo Durante, Yu Zheng, Anton Petrov, Maxim Borisyak
Olivier Schneider, Aurelio Bay, Yi Zhang, Yi Wang, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, François Fleuret, Elena Graverini, Renato Quagliani, Federico Betti, Sebastian Schulte, Veronica Sølund Kirsebom, Jian Wang, Mingkui Wang, Zhirui Xu, Zheng Wang, Lei Zhang, Ho Ling Li, Christoph Frei, Mark Tobin, Minh Tâm Tran, Niko Neufeld, Matthew Needham, Marc-Olivier Bettler, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Liang Sun, Pietro Marino, Luca Pescatore, Mirco Dorigo, Xiaoxue Han, Liupan An, Federico Leo Redi, Chitsanu Khurewathanakul, Plamen Hristov Hopchev, Thibaud Humair, Maxime Schubiger, Hang Yin, Guido Andreassi, Violaine Bellée, Maria Vieites Diaz, Olivier Göran Girard, Axel Kuonen, Preema Rennee Pais, Pavol Stefko, Tara Nanut, Maria Elena Stramaglia, Tommaso Colombo, Vladimir Macko, Guillaume Max Pietrzyk, Albert Puig Navarro, Evgenii Shmanin, Lino Ferreira Lopes, Dipanwita Dutta, Yiming Li, Hans Dijkstra, Gerhard Raven, Peter Clarke, Frédéric Teubert, Victor Coco, Adam Davis, Paolo Durante, Yu Zheng, Anton Petrov, Maxim Borisyak, Chunhui Chen, Zhipeng Tang, Luis Alberto Granado Cardoso, Katharina Müller, Xuan Li
Olivier Schneider, Aurelio Bay, Yi Zhang, Yi Wang, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, François Fleuret, Elena Graverini, Renato Quagliani, Federico Betti, Sebastian Schulte, Veronica Sølund Kirsebom, Jian Wang, Mingkui Wang, Zhirui Xu, Zheng Wang, Lei Zhang, Ho Ling Li, Christoph Frei, Mark Tobin, Minh Tâm Tran, Niko Neufeld, Matthew Needham, Marc-Olivier Bettler, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Liang Sun, Pietro Marino, Luca Pescatore, Mirco Dorigo, Xiaoxue Han, Liupan An, Federico Leo Redi, Chitsanu Khurewathanakul, Plamen Hristov Hopchev, Thibaud Humair, Maxime Schubiger, Hang Yin, Guido Andreassi, Violaine Bellée, Maria Vieites Diaz, Olivier Göran Girard, Axel Kuonen, Preema Rennee Pais, Pavol Stefko, Tara Nanut, Maria Elena Stramaglia, Tommaso Colombo, Vladimir Macko, Guillaume Max Pietrzyk, Albert Puig Navarro, Evgenii Shmanin, Lino Ferreira Lopes, Dipanwita Dutta, Yiming Li, Hans Dijkstra, Gerhard Raven, Peter Clarke, Frédéric Teubert, Victor Coco, Adam Davis, Paolo Durante, Yu Zheng, Anton Petrov, Maxim Borisyak, Chunhui Chen, Zhipeng Tang, Luis Alberto Granado Cardoso, Katharina Müller, Xuan Li