The X(3872) at CDF II

Abstract

Last year's X(3872) discovery was confirmed with the CDF II detector in pbarp collisions. We measure its mass to be $3871.3 \pm 0.7 \pm 0.4 MeV/c2$. The source of X-mesons in the large CDF sample is resolved by studying their vertex displacement. We find $16.1 \pm 4.9 \pm 2.0$% of our X-sample comes from decays of b-hadrons, and the remainder from prompt sources: either direct production or by decay of (unknown) short-lived particles. The mix of production sources is similar to that observed for the psi(2S) charmonium state.