Tetraquark interpretation of the charged bottomonium-like states Zb±(10610) and Zb±(10650) and implications

We present a tetraquark interpretation of the charged bottomonium-like states Zb±(10610) and Zb±(10650), observed by the Belle collaboration in the π±Υ(nS) (n=1,2,3) and π±hb(mP) (m=1,2) invariant mass spectra from the data taken near the peak of the Υ(5S). In this framework, the underlying processes involve the production and decays of a vector tetraquark Yb(10890), e+e-→Yb(10890)→[Zb±(10610)pi-+, Zb±(10650)π-+] followed by the decays [Zb±(10610), Zb±(10650)]→π± Υ(nS), π±hb(mP). Combining the contributions from meson loops and from an effective Hamiltonian, we are able to reproduce the observe masses of the Zb±(10610) and Zb±(10650). Our formalism implies mixing between the mass eigenstates and the tetraquark spin states. The analysis presented here is in agreement with the Belle data and provides crucial tests of the tetraquark hypothesis. (orig.)