Observation of (B)over-bar(s)(0) -> J/psi f '(2)(1525) in J/psi K(+)K(-)Final States

The decay (B) over bar (0)(s) (->) J/psi K+K- is investigated using 0:16 fb(-)1 of data collected with the LHCb detector using 7 TeV pp collisions. Although the J/00 psi phi 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 f'(2)(1525) region as well as a nonresonant component. After subtracting the nonresonant component, we find (B) over bar (0)(s) (->) J/psi f'(2)(1525))/(B)over bar>(0)(s) (->) J/psi phi)=(26.4 +/- 2.7 +/- 2.4)%.