Molecular effects in Charmonium Spectrum

Abstract

We study the influence of possible molecular structures in the charmonium spectrum. We focus on the $0^{++}$ and $1^{--}$ sectors. In the first one we coupled the $2^3{P}_0$ $q\bar{q}$ pair with $DD$, $J/\psi \omega$, $D_s{D}_s$ and $J/\psi \varphi$ channels and we obtain two states compatibles with the X(3945) and the Y(3940). In the second one we include the $3^3{S}_1$ and $2^3{D}_1$ charmonium states coupled to $DD$, $D{D}^{\ast }$, $D^{\ast }{D}^{\ast }$, $D_s{D}_s$, $D_s{D}_s^{\ast }$ and $D_s^{\ast }{D}_s^{\ast }$. In this calculation we obtain a new molecular state that could be the G(3900) or the controversial Y(4008) and two $c\bar{c}$ states dressed by the molecular components assigned to the $\psi (4040)$ and the $\psi (4160)$. The two $c\bar{c}$ states show interesting properties and in particular they solve the strong disagreement of the decay branching ratios measured by BABAR.

Comments: 4 pages. Proceeding of XIV International Conference on Hadron Spectroscopy (hadron2011), 13-17 June 2011, Munich, Germany