@article{10902/2003, year = {2009}, month = {6}, url = {http://hdl.handle.net/10902/2003}, abstract = {Evidence is reported for a narrow structure near the J/ψϕ threshold in exclusive B+→J/ψϕK+ decays produced in p̅ p collisions at √s=1.96  TeV. 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 2.7  fb-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.}, publisher = {American Physical Society}, publisher = {Physical Review Letters, vol. 102, iss. 24, art. num. 242002 (2009)}, title = {Evidence for a Narrow Near-Threshold Structure in the J/ψϕ Mass Spectrum in B+→J/ψϕK+ Decays}, author = {Aaltonen, Timo Antero and Akimoto, Takashi and Álvarez González, Bárbara and Amerio, Silvia and Amidei, Dante and Anastassov, Anton and Annovi, Alberto and Antos, Jaroslav and Apollinari, Giorgio and Apresyan, Artur and Casal Laraña, Bruno and Cuevas Maestro, Francisco Javier and Gómez Gramuglio, Gervasio and Rodrigo Anoro, Teresa and Ruiz Jimeno, Alberto and Scodellaro, Luca and Vila Álvarez, Iván and Vilar Cortabitarte, Rocío and Arisawa, Tetsuo and Adelman, Jahred}, }