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arXiv 2005.063062020-05hep-ph

A possible simultaneous fit to the available $e^+e^- \rightarrow Λ^+_c \barΛ^-_c$ cross section data nearby $ψ(4660)$ by means of a strong correction to the Coulomb enhancement factor

Antonio Amoroso, Stefano Bagnasco, Rinaldo Baldini Ferroli, Ilaria Balossino, Monica Bertani, Diego Bettoni, Fabrizio Bianchi, Alberto Bortone, Alessandro Calca… 展开作者

Antonio Amoroso, Stefano Bagnasco, Rinaldo Baldini Ferroli, Ilaria Balossino, Monica Bertani, Diego Bettoni, Fabrizio Bianchi, Alberto Bortone, Alessandro Calcaterra, Gianluigi Cibinetto, Fabio Cossio, Francesca De Mori, Manuel Dioniso Da Rocha Rolo, Marco Destefanis, Riccardo Farinelli, Luciano Fava, Giulietto Felici, Luciano Gaido, Isabella Garzia, Michela Greco, Lia Lavezzi, Stefano Lusso, Marco Maggiora, Alessio Mangoni, Simonetta Marcello, Giulio Mezzadri, Elisabetta Pace, Simone Pacetti, Piero Patteri, Angelo Rivetti, Marco Scodeggio, Stefano Sosio, Stefano Spataro

备注：: Found a bug in the present version of the work that lead to drawing incorrect conclusions in the discussion of the results

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There are two available set of data on the $e^+e^- \rightarrow Λ^+_c \barΛ_c^-$ cross section above threshold. The BELLE measurement, with ISR return, is compatible with the presence of a resonant state, called $ψ(4660)$ (formerly known as $Y(4660)$), observed also in other final states. The BESIII dataset has shown a different trend, with a flat cross section. We propose a new solution to fit both datasets by means of a strong correction to the Coulomb enhancement factor. Mass and width of the resonant state is extracted.

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