The studies of the production of the X(3872), either prompt or from B hadron decays, and of the J/ψϕ mass spectrum in B hadron decays have been carried out by using pp collisions at √s=7 TeV collected with the CMS detector at the LHC.
%The production of the X(3872) is studied in pp collisions at √s=7 TeV with the CMS detector at LHC, using decays to J/ψπ+π− where the J/ψ decays to two muons.
The cross-section ratio of the X(3872) with respect to the ψ(2S) in the J/ψπ+π− decay channel and the fraction of X(3872) coming from B-hadron decays are measured as a function of transverse momentum (pT), covering unprecedentedly high values of pT.
For the first time, the prompt production cross section for the X(3872) times the unknown branching fraction for the decay of X(3872)→J/ψπ+π− is extracted differentially in pT and compared to theoretical predictions based on the Non-Relativistic QCD (NRQCD) factorization approach. The dipion invariant-mass spectrum of the J/ψπ+π− system in the X(3872) decay is also investigated.
The search for resonance-like structures in the B0sπ± invariant mass spectrum do not show any unexpected result. An upper limit on the relative production of the claimed X(5568) and Bs multiplied by the unknown branching fraction of the decay X(5568)→Bsπ± is estimated to be 3.9\% at 95\% CL in the most conservative case.
