Search for theX(4140)state inB+→J/ψϕK+decays with the D0 detector

V. M. Abazov, B. Abbott, B. S. Acharya, M. Adams, T. Adams, J. P. Agnew, G. D. Alexeev, G. Alkhazov, A. Alton, A. Askew, S. Atkins, K. Augsten (+347 others)
2014 Physical Review D  
We investigate the decay B^+ -> J/psi phi K^+ in a search for the X(4140) state, a narrow threshold resonance in the J/psi phi system. The data sample corresponds to an integrated luminosity of 10.4 fb^-1 of ppbar collisions at sqrt s =1.96 TeV collected by the D0 experiment at the Fermilab Tevatron collider. We observe a mass peak with a statistical significance of 3.1 standard deviations and measure its invariant mass to be M=4159.0 +-.3 (stat) +- 6.6 (syst) MeV and its width to be Gamma=
more » ... +-12.6 (stat)^+1.0_-8.0 (syst) MeV. Identifying this mass peak as the X(4140), we measure, for M(J/psi phi) <4.59 GeV, the relative branching fraction B_rel= B(B^+ -> X(4140) K^+)/ B(B^+ ->J/psi phi K^+) to be 21+-8 (stat) +- 4 (syst) can accommodate the presence of a second enhancement at a mass of 4328.5+- 12.0 MeV.
doi:10.1103/physrevd.89.012004 fatcat:2gqavgcu7ffdrnrhvqgyd2lkhq