CHARM 2013: X(4260) as a Mixed Charmonium-Tetraquark State

Abstract

Using the QCD sum rule approach we study the X(4260) state assuming that it can be described by a mixed charmonium-tetraquark current with $J^{PC}=1^{--}$ quantum numbers. For the mixing angle around $\theta =(53.0\pm 0.5{)}^0$, we obtain a value for the mass which is in good agreement with the experimental mass of the X(4260). For the decay width into the channel $X\to J/\psi \pi \pi$, we find the value ${\Gamma }_{X\to J/\psi \pi \pi }=(4.1\pm 0.6)$ MeV, which is much smaller than the total experimental width $\Gamma =(108\pm 12)$ MeV. However, considering the experimental upper limits for the decay of the X(4260) into open charm, we conclude that we cannot rule out the possibility of describing this state as a mixed charmonium-tetraquark state.

Comments: To appear in the proceedings of the 6th International Workshop on Charm Physics (CHARM 2013)