A very broad X(4260) and the resonance parameters of the 3D vector charmonium state

Understand

We argue that the X(4260) enhancement contains a wealth of information on vector c-cbar spectroscopy.

• We discuss the shape of the X(4260) observed in the OZI-forbidden process "electron-positron into J/psi and a pair of charged pions", in particular at and near vector charmonium resonances as well as open-charm threshold enhancements.
• The resulting very broad X(4260) structure does not seem to classify itself as a vector charmonium resonance, but its detailed shape allows to identify new vector c-cbar states.
• Here, we estimate the resonance parameters of the psi(3D) state.