Evidence for a narrow near-threshold structure in the J/ψ mass spectrum in B+→J/ψ K+ decays

Evidence is reported for a narrow structure near the J/ψ threshold in exclusive B+→J/ψ K+ decays produced in p̄p collisions at s=1.96TeV. A signal of 14±5 events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosit...

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Autors principals: Aaltonen, T, Adelman, J, Akimoto, T, Álvarez González, B, Amerio, S, Amidei, D, Anastassov, A, Annovi, A, Antos, J, Apollinari, G, Apresyan, A, Arisawa, T, Artikov, A, Ashmanskas, W, Attal, A, Aurisano, A, Azfar, F, Badgett, W, Barbaro-Galtieri, A, Barnes, V, Barnett, B, Barria, P, Bartsch, V, Bauer, G, Beauchemin, P
Format: Journal article
Idioma:English
Publicat: 2009
Descripció
Sumari:Evidence is reported for a narrow structure near the J/ψ threshold in exclusive B+→J/ψ K+ decays produced in p̄p collisions at s=1.96TeV. A signal of 14±5 events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosity of 2.7fb-1, collected by the CDF II detector. The mass and natural width of the structure are measured to be 4143.0±2.9(stat) ±1.2(syst)MeV/c2 and 11.7-5.0+8.3(stat)±3.7(syst)MeV/c2. © 2009 The American Physical Society.