The decay B̄s0→J/ψK +K - is investigated using 0.16fb -1 of data collected with the LHCb detector using 7 TeV pp collisions. Although the J/ψ channel is well known, final states at higher K +K - masses have not previously been studied. In the K +K - mass spectrum we observe a significant signal in the f2′(1525) region as well as a nonresonant component. After subtracting the nonresonant component, we find B(B̄s0→J/ψf2′(1525))/ B(B̄s0→J/ψ)=(26.4±2.7±2.4)%. © 2012 CERN.
Aaij, R., Abellan Beteta, C., Adeva, B., Adinolfi, M., Adrover, C., Affolder, A., … Zvyagin, A. (2012). Observation of B̄s0→J/ψf2′(1525) in J/ψK +K - final states. Physical Review Letters, 108(15). https://doi.org/10.1103/PhysRevLett.108.151801