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.

arXiv comment4 pages. Proceeding of XIV International Conference on Hadron Spectroscopy (hadron2011), 13-17 June 2011, Munich, Germany