QCD sum rules study of the meson Z+(4430)

We use QCD sum rules to study the recently observed meson Z+(4430), considered as a D∗D1 molecule with JP=0−. We consider the contributions of condensates up to dimension eight and work at leading order in αs. We get mZ=(4.40±0.10) GeV in a very good agreement with the experimental value. We also make predictions for the analogous mesons Zs and Zbb considered as Ds∗D1 and B∗B1 molecules, respectively. For Zs we predict mZs=(4.70±0.06) GeV, which is above the Ds∗D1 threshold, indicating that it is probably a very broad state and, therefore, difficult to observe experimentally. For Zbb we predict mZbb=(10.74±0.12) GeV, in agreement with quark model predictions.