Production rates of Ds plus Ds- and DD? molecules in B decays

Motivated by the recent discovery of a charmonium X(3960) in B decays by the LHCb Collaboration, the likely existence of two bound/virtual states (denoted by Xss over bar and Xqq over bar ) below the D+s D-s and over bar DD mass thresholds has been reexamined recently. In this work, we employ the effective Lagrangian approach to calculate their production rates in B decays utilizing triangle diagrams. Our results show that the production yields of B+ -> Xss over bar K+ and B+ -> Xqq over bar K+ are of the order of 10-4, in agreement with the relevant experimental data, which indicates that, if the D+s D-s and over bar DD bound states indeed exist, they can be detected in B decays. Moreover, we calculate the production rate of B+ -> X(3960)K+ assuming that X(3960) is a resonant state of D+s D-s and find that it is also of the order of 10-4 but a bit smaller than that as a D+s D-s bound state.